Bitcoins aren't just an abstract financial instrument living somewhere in the digital ether anymore. They're now a physical currency capable of taking a ride in your pocket or scratching off your lottery tickets.
The physical Bitcoins, called Casascius Bitcoins and created by a guy in Utah named Mike Caldwell, are made of brass, with gold electroplating on the 25 Bitcoin denomination. And, of course, they're tied to the peer-to-peer, open-source digital currency that's been exchanged on the Internet for a while now.
Each coin has a unique Bitcoin address and a redeemable "private key" under a hologram on the coin. That key can be used to redeem the value of the Bitcoins online, but the hologram sticker leaves a honeycomb mark when peeled back, so you'll know if your Bitcoins have been tampered with.
The coins play a function similar to a gift card or certificate with a magnetic strip or bar code. In other words, it provides a tangible means of carrying around the digital key that contains the actual value. There's just one problem--the physical Bitcoins may well be illegal. … Read more