[possibly some time in the future]

I'm planning of asking a shop in my region about accepting bitcoins.  They have both an online shop and a bricks&mortar selling location, and they would be the first to accept bitcoins in the wider area.  Furthermore, I believe they could be a perfect fit because the shop owner is almost famous for his creative, experimental and unconventional ideas (which are also the reason for his success), so that I can well imagine the idea of bitcoin appeals to him not only if he thinks it would make more profit, but simply because of itself (not needing any middle man for transactions, for instance).

Even more, the business is getting its raw materials (fair trade cocoa beans) directly from suppliers / farmers all around the world (for instance india or south america), with the founder visiting local communities and fair-trade sponsored social initiatives himself from time to time.  So possibly some time in the future (when supporting infrastructure like exchanges have grown in those countries) it could even be an interesting option to buy supplies (partly) with bitcoin.  This would even solve the "problem" of getting bitcoins to argentine, which has been discussed here already a bit, and could further help locals.

So all in all, as mentioned already, I believe this particular business is really perfectly suited for bitcoin adoption - maybe I'm biased, but at least I can't think of one in my area which would fit better.  I plan to write them a mail, asking whether they already know about bitcoins and highlighting some of the key properties and why I think it could be interesting to them.  If there's really interest and they take the time for it, I would also be delighted to personally visit them and give a short introduction or so.  I'd like to get some suggestions about what exactly I should point out in my message:

• Of course, for a shop bitcoins offer the possibility to accept payments rather easily (with a printed QR code + computer, or a tablet running one of the mobile wallets), (mostly) without fees.  However, where I live credit cards are not that common (more ATM cards), so I doubt that there's really the potential to save 3%+ of fees on most purchases.  Also, the local currency are Euros - is there a similar service to bitpay available, in case the merchant prefers to avoid the exchange rate risk?
• As mentioned, I can imagine the business owner could be interested also in bitcoins ideals (somewhat).  So I suppose it would be a good idea to point out the key features quickly (no middle man / no central authority, basically "freedom of monetary transactions").
• It would be at least an initial and also PR boost to be the first place in the wider area where one can actually spend bitcoins in person, and possibly the first to accept bitcoins of its business sector in a rather wide range (Austria / Europe? / world-wide? when the sector is defined accordingly), which would probably be an additional incentive.
• Do you think it would make sense to also mention the possibility described above of paying world-wide supplier communities directly with bitcoins?  I can see this as interesting option in the future, but certainly not yet.  But if the business owner is far-sighted (which he is, IMHO) I can imagine this could also interest him as possible vision for the future.

What do you think would be the best things to inform them about?  I'm really excited about this, to be honest, since I would also personally love to spend my coins there.

I would be interested what the Bitcoin community thinks about recent (and not-so-recent) developments in Austria with respect to activism (and in particular, animal-rights activists).  In principle, we Austrians see our country as "free" and "democratic", but since I got a little more involved in these subjects, I'm no longer any confident (much like a lot of people write here about the US).  For instance, the "Tierschutzcausa" (see http://www.guardian.co.uk/commentisfree/2008/jul/18/animalwelfare.animalbehaviour or https://de.wikipedia.org/wiki/Tierschutzprozess (in German)).  Activists were persecuted for colluding in a criminal organisation for legal protests and some acts of crime, which - as they found out later - were not committed by them.  They were initially arrested with massive police raids on their homes, were spied upon to great lengths before that, and some 10 millions of Euros of tax payer money was wasted on the persecution.  In 2011, all charges were dropped.  However, the judge who did that was removed from her post, and instead the persecutor got promoted (in Austria, in particular one major political party is heavily related to industry owners (including who earn their money on animal products or by selling fur clothing), owners of big agriculture businesses and (part-time, for fun) hunters).

Furthermore, the Austrian institution for protection of the constitution devotes a lot of space in its annual report to "extremist animal rights groups" - and because there was not a single crime to report about, they instead listed charges like wrong parking at legal demonstrations, instead of simply not pretending that the particular animal rights group in question (the VgT) was a danger to the constitution.  In fact, it can be argued that the merciless (and baseless) persecution of legal demonstrations as well as heavy police presence in particular for animal rights protests in itself is danger to the constitutional rights of free speech and expression, as well as demonstrations protected by the constitution.

Now the highest appeal court ruled that some of the actions had been coercion:  Namely to let businesses know of (legal!) planned campaings informing their customer about (truthful) facts relating to their business.  The logic is like this:  By informing the customers, they might not any longer want to buy at that particular business, hurting its profits.  Thus by using this to "pressure" the business into not selling fur any more (or whatever else you want from it), you commit an act of coercion according to Austrian law.  This is a completely wrong ruling and surely against the spirit of the law as seen by the broad majority of the population.  In fact, if that was indeed true, it would open the door widely for anyone to persecute any NGO which is unpleasant to one's interests, turning the democracy into a police state.  See http://www.vgt.at/ for a lot of news about that.

In response, there's now a bid to charge oneself with coercion because of legal protest actions taken, in order to show how insane this understanding of the law is.  Already more than 900 curageous citizens submitted it, it will be interesting to see what the general persecution does on this.  However, I really have to admit that I was shocked to notice how I hesitated in supporting that bid because of fear for the consequences ... and precisely such fear (despite being in a nominal "democracy") is what the ruling elite wants to achieve in order to discourage the general population from claiming their rights in a supposedly "free" society.

What do you think about that developments?

BTW, I already asked the VgT whether or not they would want to start accepting BTC donations.  (Which I would love to give.)  So far no response, though.

I've been thinking recently about switching over to a bitcoin accepting web hosting.  I need a VPS with Debian (or Ubuntu) as operating system, at least 50 GiB of disk storage and ideally unlimited bandwidth (or at least around 500 GiB / month).  I don't need so high server performance, but it would be good if it could run bitcoind without problems in addition to a web server.  Extra bonus if I can have more than one IP address, either included or for a (not too costly) extra price.

The problem is that most offers I have seen only give high / unlimited bandwidth together with expensive high performance packages, while my current hoster allows me unlimited bandwidth also with a relatively cheap contract (less than 0.1 BTC / month).  Does anyone know of a hoster which satisfies my requirements while being in about that price range?

I'm working on a project which will require users to sign server-provided challenge messages with the private key of one of their addresses.  Since a signature with that key is basically also what allows to spend coins from that address, I want to be sure about the security implications for my users.

Assuming a user can be tricked to "signmessage" arbitrary strings provided by an attacker, can this be used to spend the user's coins?  I presume there is some safeguard in the protocol such that the data signed with signmessage is of a different "format" than signing of transaction outputs ... is this the case, or can a message be crafted such that the signature on it can be recast in a form to validate spending a transaction output?

Of course my server is not going to issue rogue challenges to sign, but before I tell people to sign randomly provided strings and make them used to it, I want to make sure this can't be used to attack their coins.

Ich nehm mir mal die Freiheit, einen Thread über Namecoins aufzumachen.  Ich finde ja schon länger die Idee, nicht nur Domains sondern auch persönliche Identitäten (id/xyz) registrieren zu können, sehr spannend.  Insbesondere kann ich da meine öffentlichen Schlüssel ablegen, so dass sie von jedem überprüft werden können.

Eine andere meiner Meinung nach spannende Idee ist es, Logins auf Webseiten über id/ Namen zu machen.  Im einfachsten Fall könnte man ja mit dem zum Namen gehörigen Schlüssel eine Challenge-Nachricht des Servers signieren, um sich so einzuloggen.  Dann gibt's kein Passwort, auch nichts, was ein Hacker stehlen könnte, der den Server knackt, und wenn auch noch Walletverschlüsselung für Namecoin im Mainstream ist, hat man quasi eine kleine 2-Factor-Authentifizierung:  Was man hat (die wallet.dat mit dem Schlüssel) und was man weiß (das Passwort dazu).  (Mir ist schon bewusst, dass Malware natürlich "auf einmal" beides abfangen kann.  Das ist aber auch nicht der wichtigste Aspekt bei dem Ganzen.)

Im Grunde schlägt diese Idee für mich in die gleiche Kerbe wie OpenID - man muss sich nicht extra bei jeder Seite anmelden, sondern kann mit einer Online-Identität überall teilnehmen.  Seht ihr das auch als sinnvolle Anwendung von Namecoin?

Außerdem hab ich mir gedacht, ob man nicht der Verbreitung ein bisschen auf die Sprünge helfen könnte, indem man es mit OpenID koppelt - ich weiß bis jetzt nur vage, wie OpenID funktioniert, aber ich hoffe mal, dass es wirklich so funktionieren könnte:  Soweit ich weiß, funktioniert OpenID ja so, dass die Seite, bei der ich mich einloggen will, mich an meinen Provider weiterleitet, ich mich dort einlogge, und dann von diesem authentifiziert werde (mit einem Cookie oder sowas?).  Könnte man nicht einen OpenID-Provider implementieren, der es erlaubt, sich mit einem id/ Namen einzuloggen (nach dem oben beschriebenen oder einem ähnlichen System)?  Wenn man dann auch noch das Signieren mit dem Name-Schlüssel automatisiert (mit einem Browser-Plugin oder so) könnte man sich damit dann auf einmal mit Namecoin bei vielen großen Seiten, die OpenID akzeptieren, einloggen.  Das könnte der Akzeptanz weiter helfen.

Was haltet ihr davon?  Wenn das nach einer guten und machbaren Idee klingt, würde es mir Spaß machen, an so einem System zu arbeiten.  Es würde dann frei (GPL oder vergleichbare Lizenz) werden, und idealerweise auf einem Hauptserver komplett fertig zur Verwendung installiert sein.  Es geht mir dabei nicht darum, Geld zu verdienen (Spenden in BTC oder NMC sind natürlich trotzdem gern gesehen), sondern einfach darum, eine meiner Meinung nach interessante Idee auszuprobieren.

[without compromising my anonymity]

With things like Zerocoin or (realistically for a not-so-long time frame) P2P mixing on the radar, I was already thinking about how I would use those to enhance my anonymity when there will finally by some people accepting Bitcoin near me in the future.  The scenario I think about is like that:

* I have some total balance on my wallet (except what is in cold storage for long-term saving), where I assume it is not at all anonymous because parts may be from my public donation address, exchanges have my identity because of AML regulations, or because I posted with my real name on a local group mailing list asking to buy in person and at least the seller now has my real name plus Bitcoin address.

* When I now make some purchases, I don't want the seller to know who I am / how many Bitcoins I have in total / things like this, and I also don't want the public to know what things I buy, assuming the receiving address of some business I shop at is public.  (For instance a printed QR code in a pub.)

* Thus, having Zerocoin or some P2P mixer, I decide to run 1 BTC through it and cash out at a fresh wallet (possibly on my mobile phone for easier spending on-the-go).  This has to be some "standardised" amount, though, I can't do it with 0.182673 BTC.

* Now I have 1 BTC to spend on some purchases.  While it will be possible to link together all items I bought with that 1 BTC, it won't be able to determine who I am, how many Bitcoins I have beside this balance, or what else I bought before that "1 BTC batch" or what I will buy afterwards.  This is acceptable privacy for me.

The only thing I can never really work out is what to do when the amount remaining of these 1 BTC is no longer enough for more purchases.  Say I spent some 1 BTC batches already, and from each of those 0.01-something BTC remained as final change.  Thus I end up with some coins spread accross multiple wallets.  Is there any way to reconcile those into a combined balance, so I can make use of them again, without compromising my anonymity?  Or is all I can do then donate anonymously to some charity accepting Bitcoin?

The problem I see is this:  As soon as I generate a transaction with inputs from those balances, even if it was just again to "mint" a 1 BTC zerocoin, it would become public that in fact all those 1 BTC batches were linked to me (or at least to each other).  However, it is also not possible to anonymise each change balance before that, because I have to send some standard amount to the mixers ... and it would probably be hard to find "mixing partners" for my change amount, right?

A possible solution I see would be to have an account at a "centralised mixing site", say some online wallet or even the Silk Road or something like that.  I could then send my change back to it at new addresses each, and when my balance exceeds 1 BTC again, withdraw a full Bitcoin to mint a fresh zerocoin with it.  Then probably only the site operator would be able to link everything to me.

I hope I could explain my thoughts clearly ... sorry if it sounds confusing.  Do I miss some important points, or is there really no nice solution for this problem with things like Zerocoin or P2P mixers?  I'm curious about other thoughts about that!

In my opinion, a general time-stamping service would be of great utility at times.  I'm aware of some projects that try to utilise the Bitcoin blockchain for that purpose, by sending coins to addresses based upon the hash to stamp or encoding the hash into amounts sent or things like that.  While that works, I don't think it is a good idea to abuse Bitcoin for that purpose.  After all, it was made for payments and not general-purpose time-stamping.

So instead, we could set up a genuine service <b>only</b> for time-stamping, with a separate blockchain.  It could work similarly to namecoin, with merge-mining to get easy hash power as well as a dummy currency that can be earned by miners, possibly traded a little but whose main purpose is to pay the network for special time-stamp operations.  (Either in form of a network fee as with namecoin or just by transaction fees.)

What do you think about that, would that be a useful project?  (Opposed to all nothing-at-all-changed altcoins that are only used for speculation.)  I think it is a useful thing to have, and it would be good to keep such things off the Bitcoin chain.

[lots]

Hi!

I've already been some time into Bitcoins, but this is the first time I want to "officially" turn towards the community.   I've used (and am using) a lot of give-away sites, not because I think they really pay off but more because this is kind of addictive and also fun.  However, due to that and lots of small transactions building up my funds, I was shocked one day to find a transaction ate up about BTC 0.05 in transaction fees....

In order to help prevent accidents like this in the future, I wrote some small scripts that can be used to create transactions "combining" your unspent transaction outputs into larger pieces, until in the end your whole balance is made up only of a single transaction output that can be used to send coins for free and with a small transaction.  The scripts are not intended to be used by people not understanding exactly what they do and I wrote them mainly for my own use, but also want to share them here in case someone finds them interesting and useful:

  http://www.domob.eu/projects/coinCollection.php

However, use at your own risk!!!

I'm happy about comments and ideas, although I'm currently not planning to spend many more time working on them.  But who knows?

Yours,
Daniel

PS: I think some people might consider these kind of scripts to be "spamming" the blockchain, but since Bitcoin is decentralised, the nodes collectively decide upon a policy for determining which transactions to accept and which to reject because they may be spam.  The whole purpose of these scripts is to build only transactions that are considered acceptable, and they are also not intended to automatically run and generate transactions all the time but rather be called manually only from time to time, so that not too many transactions are generated at a time.