I run the risk that someone loads 10000+ BTC on it and then uses sophisticated/expensive means to attack the piece to somehow get the private key while keeping it appearing untampered.
Just a FYI, At this year's defcon conference (and previous ones) they had a room with all kinds of tamper evident devices and prizes for defeating the devices.
I believe every device was defeated with low-tech methods. Most of them that were plastic simply involved warm water.
I think a paper note might be less susceptible to some of the methods used though.
I have tried and tried and tried to remove a sticker from my notes without evidence. No luck.
I thought the same thing, given that I have attended DefCon every year for the past several years and am amazed that even as sophisticated as tamper evidence gets, there's always somebody out there somewhere who knows how to crack it.
Someone with 10000 BTC to throw at a potential scam would be in a budgetary position to imitate my hologram from scratch, regardless of whatever could be done to compromise it without being detected.
Meanwhile, if I could produce a good legitimate 2-factor key product, complete with engraved bitcoin address and all, I anticipate a possibility that it might attract the interest of financial professionals wanting to store bitcoin, such as officers of corporations or asset managers. It would be a credible and safe way to store bitcoins without having to trust anybody but the person in possession of it, and to the right audience, would be well worth the $35+ I'd have to charge per piece to make it worthwhile, given that each piece would be custom.
