If you're interested in getting into Bitcoin mining, there are several ways to do it on a Raspberry Pi. This particular setup makes it extremely easy if you use USB devices about the size of a flash drive (with a powered USB hub) called Block Eruptors.
formatting link
It's actually not profitable at this point to do Bitcoin mining this way
- regardless of the number of the USB devices you hook up - but it's another interesting area to explore with your Pi. :)
- Trevor