Quote from: casascius on September 11, 2012, 10:17:04 PM

Quote from: MyBitcoinMint on September 11, 2012, 09:57:05 PM

Very true. Our goal is slightly different, because we are trying to completely remove the counter-party risk of having someone else create and be in control over your public + private key at any point. Now I'm no computer whiz, but after consulting with nerdier friends of mine, I believe it is possible to develop an app that can create a public and private key, and transfer those keys to an NFC chip. This would mean we could sell the NFC chip / Physical Bitcoin, and the customer would be able to create and export the private/public keys on their own. Thus, customers would not have to trust us and our ability to keep their keys a secret (or steal them Shocked

).

Just to play devil's advocate: you're right that the customer would not have to trust you, but someone receiving a loaded coin from somebody other than you would instead have to trust whoever loaded the key - someone they will never be able to identify let alone take action against in the event of a fraud.

A user could already remove the counter-party risk on a Casascius coin, simply by printing his own private key on a round piece of paper like I do, attaching it to the coin under a round sticker of his own choosing, and funding it himself. But by doing so, his coin would not have the property of being spendable to somebody else who doesn't trust him, because that next party has no independent way to know who generated the key within it and/or whether they still have a copy of the key.

Using NFC or RFID or any other similar technology in place of the paper doesn't improve on that problem in any useful way.

Hi Casascius! Always glad to have your input.

Agreed, a person-to-person physical exchange of these coins definitely has the trust problem. However, my main goal with this project isn't for these coins to be traded, but rather maximize the security of the public/private keys for the customer. With all the hacks Bitcoin has had, in particular the last few months, I think a product that the average person can both physically hold and also trust is an important product for timid Bitcoin noobs as well as serious Bitcoin investors looking for a safe, secure method of storage devoid of counter-party risk.

Now I'm not sure if this is possible (you'd know much better than I would), but I would also like these NFC-Physical Bitcoins to be able to transfer a limited amount of Bitcoins to another NFC-capable device, such as a friend's cell phone or your own cell phone. Say you had 1,000 BTC stored on your secured NFC Physical Bitcoin, but wanted to transfer 5 BTC for use on your phone or to pay a friend, these NFC devices could get around the 'trust' issue by directly transferring the coins between NFC devices.