Bitcoin Forum

What do you think of the idea of using scratch cards (about the size of a business card) as cheap physical Bitcoins for in-person trading?

They are relatively cheap to make (about 25 cents each, maybe even cheaper with a large scale) so there would be little overhead.

The private key would be hidden under the scratch surface.

I would imagine using them mostly for small denominations in the 1-20 mBTC range.

If people are interested I would start this project. I would only need some nice graphic designs for the cards.

Hi, I think this is a good idea, would like to discuss with you more.

I think that's fine as long as their value is pretty low, because counterfeit would be pretty common otherwise.

I agree, their value has to be relatively low. Not more than a few mBTC. The long-term idea is that these could also be used in developing countries.

The risk any potential counterfeiter would have though, at least for in-person trading, is that a person checks for the private key on the spot.

Sure. You can PM me if you like.

I would be willing to setup a website.

What I would mainly need first are some nice designs.

I'm thinking of running a crowdfunding campaign after that for the initial print run (also to gauge the level of interest).

After that I would be willing to organize the printing of the cards (unless somebody finds a cheaper way of printing)

why crowdfunding?
you can go at it with an investment as little as 500$

search for it (protip: alibaba.com )
you can get 10k scratch cards for 100$ or less

this is very straight forward, either you do it with your own capital or you don't. Also I doubt you can get a patent for it , so if you present it to a real investor he might aswell do it on his own, if you put it on crowd funding for so little money, they will just laugh at you.

I think I can help with printing cards in needed quantity. This would be like prepaid mobile phone card. The design can be under all rights reserved. And nothing to conterfeit here cause they have a unick code. I will help with that!

Thanks, that would be much appreciated.

I was also just thinking that they could basically have the same format as a prepaid mobile phone card.
The area underneath the scratch would need to be big enough to hold a Bitcoin private key though.
Also each card would need to have its public key printed on it (with a QR code if possible).

It's not only the amount of money necessary to fund. If it's up to 1000$ or so I could indeed fund it myself.

I was also thinking of it as a means to gauge the amount of interest in it.

If I go to Bitcoinstarter.com it will be one on the bigger projects funded there.

That's can be done. The code under scratch layer just like mibile prepaid. They can be colour printed with design. I think I can talk to David Smit and he will make some great design for them. What investment are you ready to put in them?

About 2 BTC at most out of my personal money.
But it also depends on how many you can print then.
Maybe I can get more from crowdfunding, too.

For 2BTC I can print around 18000 of them. Standard size, 1-side laminated, face colour and back 1 colour with scratch panel just like prepaid mobile. But some money need to be for funding them!

dude, you can print them in china for way way less.

Sounds good.

I assume the scratch would be big enough to a private key (30 characters).
Would that include several runs (3 or 4) for different denominations (each with a different color/design)?
Would "face color" mean that a full color design is possible?

Is there a website I can check for this printer?

Probably 0,5 million ordered in China will be cheaper but not 5000 that is definately.

Printer is in Ukraine. Any amount can be printed. The bigger amounts the less price. The scratch area would be big enough to hide a key.
Several runs are possible with different designs and denominations. Face is full colour printed. Actually they can be 2-sided full colour but it's a little more cost!

Sounds good.

Does this company have a website I can check?
Or else you can give me some contact info? You can PM me with that if you like.

There is a bit of a trust issue here, so I would like to personally know this printer.

What is than for me? I also want to participate in that!

Well we can make/design them together. I need designs and I need a program that generates the private/public keys and embeds them in the images.

I was thinking of using this key format:
https://en.bitcoin.it/wiki/Mini_private_key_format

I will also need a website, if you would like to help with that.

If you have personal contact to the printer that would be good too. Because I need to be able to trust the printer.

If you can also supply funding for the initial print run, then we can divide up the print run accordingly (and make it cheaper per card).

Mini private key should work.
For design I will ask Smit to make something graphical. Can help with print. This is a trusted printer. Webmoney print their scratch cards at him.

Well, I wish good luck to the project.
Mageant, if you are going to do it, commit to it. do some research, 0.1$/card is not a bad price, but you can get better if you do search.
Also, be careful on how are you going to profit with this, evaluate your costs and your added value to get your price.
On another side, get a graphic designer, pay him for the design and you are good to go.

PD:you can and should put both the public and private keys on QR codes

We can use this program from Mike Caldwell to generate the keys:
http://casascius.wordpress.com/2013/01/26/bitcoin-address-utility/

We could also modify the code in the program to suit our needs.

What about making them folded and cliped so the key is hiden inside to avoid scratch panels and share information. Folded and cliped can make myself of good quality and quantity and secure. Everything is between us.

  I made a cheap one just for handing out as gifts and stuff and as a bit of a test.

https://i.imgur.com/CPWWuBMl.jpg

I would like to see them done "professionally" though.

I don't quite understand.
What do you mean with "folded and clipped"?

Do you have an example of how that would look like?

They lool like that:
http://pixs.ru/showimage/vaucherjpg_2167345_10493279.jpg (http://pixs.ru/showimage/vaucherjpg_2167345_10493279.jpg)

Hm, sorry, I don't think that's what I want.

Scratch cards can be made but as for me I not about sharing too much sensitive info but it's your idea so it's up to you to decide