Bitcoins get real as physical currency launches
It's the perfect gift for the geek who has everything: 'real' Bitcoins you can hold in your hand, but which still function as legal tender for the online, open-source currency.
Bitcoins are familiar to many as the peer-to-peer 'cryptocurrency' that can be sent over the internet without the need for a bank or payment service - but until now, they didn't exist. At least, not physically. But thanks all changed thanks to an enterprising man from Utah.
Mike Caldwell has created Casascius Bitcoins - physical coins, available in denominations of one and 25 Bitcoins. According to Caldwell's website, each coin has its own Bitcoin address and a redeemable 'private key' hidden inside. The 25 Bitcoin piece is electroplated with real gold, measures 44.5mm in diameter by 2.9mm thick, and weighs about 35 grams. The 28.6mm one-Bitcoin piece is made from solid brass, and weighs around seven grams.