I use them from time to time to purchase things on the Silk Road. Wouldn't keep hold of them for too long though, the value fluctuates far too much. They've tripled in value in a couple of months but have also dropped in value just as much in the past. For anyone wondering what they are, they're simply an electronic currency. They bypass the need to use any regular banking system thus avoiding any charges and are almost untraceable by the authorities. Great for people wanting to buy things they don't want people knowing about