Over the holidays, I spent many hours reading up on bitcoin, and I was struck by just how large the ecosystem and variety of players was. Putting aside the debate around bitcoin's value, I think there is no debate that this is an intriguing and very very interesting space.
As an investor, I'm bullish but cautious, as a hobbyist I can't stop reading about it.
(By way of disclosure, I own a very small number of bitcoins. Also I'll tell you about a bunch of services I've played with but I can't vouch for them beyond a cursory examination. There are certainly fraud and theft concerns in the bitcoin universe so caveat emptor.)