Some friends have been following the development of that Bitcoin currency -
http://bitcoin.org/en/ It looks like a good time to get involved. All the software will run on Linux; in fact, Bitcoin is open-source - free to download, and free to modify/improve if you are a software developer.
I'm looking at it now, determining where to start with the large selection of software options, and in what direction to develop my activities.
Anybody here have experience with Bitcoin?