Quite controversial at the moment. Partly because Indian authorities are examining it as a form of tax avoidance, partly because there are questions about whether bitcoin is 100% wise and partly because various tea identities are having a slanging match over it.
I figured this would be an appropriate topic to respond too. A few days ago a new coin like bitcoin was released called Teacoin. The idea behind it was to pay respect to all different types of tea. Right now it seems to be a social experiment but it looks like it is picking up some steam in the bitcoin community.