The Rokos Core, now in its fourth version, is a disk image for Raspberry Pis that can turn your single-board computer into a full bitcoin node. The system will allow you to hold a bitcoin wallet and mine, send, and receive bitcoin over the network.
Understand that without specialized hardware this thing is essentially the way to actively waste electricity and/or hold bitcoin. However, because it is a full BTC node, you’ll be doing the bitcoin world a favor while learning a bit about mining.
The best thing, however, is that the Rokos has a full GUI and point-and-click interface. This means that folks who might not want to futz around with the command line can play with bitcoin. For example, earlier systems used CGMiner, a fully-featured if difficult mining system while 21’s mining rig is baffling to newcomers. If bitcoin mining can’t be profitable it should at least be fun and/or easy.
So download your disk image, burn it up, and get started on the road to cryptocurrency hegemony. Satoshi will thank you.