If you've never heard of bitcoins, they are a decentralized digital currency based on an open-source, peer-to-peer internet protocol. It was introduced by a pseudonymous developer named Satoshi Nakamoto in 2009.
Today was a big day for bitcoins for two reasons; the U.S. Financial Crimes Enforcement Network (FinCEN) released the US Treasury Guide on Virtual Currencies. But more importantly it's the first day they traded over $50 per $1USD!
If you want to get started with bitcoins, check out the weusecoins.com Getting Started page.
If you want to practice using it, you can send me a fraction of a bitcoin at my bitcoin wallet address: 1P2qXeETYqf7b9XnkDjdqKmFZsEtuoJty6.