As stated, the only real issue you'd have with the hardware of the calculator is keeping track of time.  TI89 has a real-time clock, and the backup battery (beneath the AAAs) will keep this running.  The main concern is that you likely do not have efficient means of keeping the clock synchronized to a network time.  Google's newest release of the app now even contains its own NTP task to fetch a time rather than using the phones. I haven't looked into it, but given the app, and the pseudo-code you posted, your grace period is exactly 30 seconds.  How long you have remaining (the countdown in the app) is controled by the modulo 30 of the time seed used.  I would expect that there are open implementations of SHA1 and the necessary hash functions you need in TI-BASIC89.  Really should be quite simple to implement, just need to make sure you check that your clock is accurate fairly regularly.

There have been proposals for functionality matching what you are looking for in a new namespace throughh the namecoin blockchain.  http://dot-bit.org/Messaging_System

You would be better off in most cases encrypting the wallet off to the flash disk and keep the blockchain on a machine with a decent disk.  Symbolic linking is your friend, mount the drive and symlink wallet.dat into datadir.  A lot of unnecessary writes going on if you are fetching the whole chain to a flash drive.

There is really no way to justify theft claims in most cases, therefore something of this sort is less than feasible.  It's all subject to trust in the previously controlling figure in their claim.  At least 'loss' is an easy claim as if at any point claimed lost coins are spent, the obvious fact is they were truly not, but stolen...

Could have something on the sort of the address that held them signing a note that the coins were stolen and others signing the claim in trust, but the infrastructure for such is obviously not implemented in BTC chain.  namecoin could be used to follow such, or really any sort of other pub forum.  But either way, attempting to quarantine stolen coins in most sectors of the market is extremely problematic.  Not terrible when Gox and the like do it, but if nodes start trying to block stolen transfers, things will clearly become problematic fast.

Example of the last comment if some are not yet seeing it:  A number of coins are stolen and end up being distributed heavily before discovery of the incident, someone with even 2-3 satoshi attempts a larger transaction including these coins they now own.  If a number of nodes at this point were to say these coins were known stolen and attempt to quarantine them, the 'thieves' have already profited and network users are impacted negatively.  Further to this point, if anything managed to get implemented on a large number of nodes, someone could 'Robin Hood' and distribute a large theft across a list of public addesses immediately, before any detection algorithms could identify and validate a theft and effectively destroy the network.

The only valid solution is to safeguard owned coins, and not to attempt firewalling cures on the network.  Obviously I've gone further than the previous queries here, but worth consideration.  These concerns could be mitigated by a client implementation with wallets acknowledging a trustnet of what coins should be purged from the network, but then we're just throwing away marketable coins, which is foolish at best.

The real issue up to this point is that there has been more market drive for solutions with more functional blocks than ALUs.  I expect this will change heavily within a year if we levy some of the major silicon suppliers, or some of you that have been in this from the beginning set up a business model that could rival the giants.  FPGAs and ASICs designed with mining in mind would offer substantially better margins than any equipment out there now.

As far as GCN goes, I have a tahiti, and have not found it to be substantially more efficient with current software options,  Of course until you an get a transistor by transistor map of what is in a chip, there's little to be said publicly about how to improve an option.  Though bitcoin mining of course favors clean manipulatable logic cells over all the fancy bits in modern silicon solutions.

Do what you like as you were closing the offer.  I signed your key on pgp.mit.edu for good measure.
Address in sig.

Take what you will, each are as easy as another.
https://i.imgur.com/WN9Dv.png

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Same could be said of anything.  There is no system that can fully insure transactions made with different currency/items.  There are some interesting use cases with loosing funds on the network with hashes that cannot be resolved by either party until they agree on a transaction, but this assumes that the involved parties would sooner work together to ensure these coins are not lost than to abandon claim.  And it can only work with purely digital transactions...

There have got to be better ways to manage this.  I've spent hours reading threads and related links, then click back to check another thread, or look to respond to something and can't due to this status.  The due to inactivity from not actively refreshing, gained no recognized time...

$.01 / hour >> calc .05 BTC /hour.  Based on one machine I was playing with at similar rates, you're probably looking to average no more than 1 share / 2 minutes. Contributing to mining pools, that won't be a profitable return, most on the order of .0004 (estimate, haven't looked in a while, and veries based on block luck) / valid share.  Take that on your own, and it's a gamble, but the odds aren't in your favor.  Now taking into question efficiency or ease of translating USD to bitcoin through this method as opposed to others, and estimating long term value of BTC, this point could be argued, but frankly, no.

The send operation is done by looking at available coins tied to all permitted addresses you specify, and from here, these are grouped in a transaction and sent to a receive address.  As such, it is clear to one who examines the blockchain exactly where sent funds are coming from.  That said, if you have multiple addresses tied to different identities, if you are not careful in how you specify a transaction, one could link the addresses to one individual, and if you are dealing with personal information to anyone you were involved in a transaction with, they could tie that to an individual.

Back to your query specifically, the answer outright is yes, that will be easily possible if you simply  receive the coins and send them later;  there are countless ways to obfuscate this, however, if you were so inclined.

#2 is a decent model in that it prevents unnecessary traffic on a wallet only standpoint, but this falls back on a central 'bank' server which is hardly ideal. Analogy is not accurate, I grant. Curiously, I've just considered a resolution to this issue outside of the proposed norms that could potentially have great merit.  Will have to explore that further when I doff this newbie pall.

366534

Rather vital.  If you don't verify your blockchain, you could both have misrepresentation of your available funds, and your being an unreliable node would bog down the network.  Of course if you have a node you trust with absolute certainty, you could pull the blockchain from that machine directly (outside of the client) but even this is not ideal.