Thank you all for your feedback.
SummaryIf this was used as intended, which is not as a collectable, but as a form of money that would circulate from person to person until it was taken out of the economy, it is possible it could face a number of attacks along the circulation path:
[ul]
- one agent could remove the hologram, grab the private key, reapply the a new hologram, and pass the bill off and take the funds at a later date.
- The alternative method is that a funded bill is copied many times and distributed with again the same generic hologram.
[/ul]
DeathAndTaxes presented a more challenging attack, which was with a custom hologram, the bill could be dissolved, and the hologram could be applied to a copy of a bill that was already funded. Being that this is archival quality paper, and the hologram does a darn good job of holding on to the cotton fibers, I am not sure this is a meaningful attack vector. Keep in mind the hologram covers both sides of the bill in a sandwich.
He also presented the idea of bleaching out the unfunded public qr code and reprinting a funded public qr code. This seems a little more possible, but the paper isn't linen, it is pressed cotton. It won't survive a washing machine cycle for example, though the private key hologram sandwich would likely survive. It will likely survive a simple bath though. I'll have to do some experiments with bleach to test this out, since this seems like the one way that the custom hologram would become nullified.
If the hologram was lazer etched with the value and the bill was already funded (not funded by the first owner of the bill) DeathAndTaxes' second argument would become moot. Essentially the bill would be the hologram sandwich, and everything else would be fluff that makes it more money like to new users.
ResultAll orders are being refunded (I am contacting users to see what addresses to direct funds to). None of the bills have been circulated, and that is for the best. The denominated bills will not be available for sale until a custom hologram is produced that would be difficult to clone.
I think the design with the non-custom holograms is acceptable as a personal check (or cheque) that is from one individual to another. I will be taking the open/non-denominated bill and tweaking it to make it more cheque like, and removing the suggestion on the back that this is something to pass around. I'll post up the design for you guys to look at.
My mission is still to have denominated bitcoin bills. I think physical cash is a vital part of bitcoin. It needs to be low cost, secure enough to pass through many user's hands, and easily convertible back to bitcoins. I want to make it look good, but I don't want it to be a collectable (it can be, but that is not a goal). I want people to be making transactions with bitcoins without any access to electronic devices, and with the same redemption qualities as gold & silver bills printed long ago. Basically a very user friendly currency that is backed by something that is valued and is uncontrolled by any government.
A little helpI need to get a sense of if anyone is interested before investing in this. If the bills had a 0.45 BTC markup (at current bitcoin/dollars) over actual denominated value how many would you buy? Please send a PM to me with what you would like.
Also, if anyone would like to buy in bulk for reselling let me know as well. I can do custom promotional bills.
Thanks,
Rob