Many of you may have heard of BOINC, but if not, let me clarify:

What is BOINC?

BOINC, or Berkeley Open Infrastructure for Network Computing, is a system where a large group of computers all contribute spare computing power to perform a task. This spare computing power is widely used to fight diseases, like cancer, or multiple scelerosis. It is a very useful took for universities and charities, since they can get a large amount of computing power to help them with their research.

Why should I care?

We all have that spare laptop or computer lying around, or sometimes leave our computers on at night, or just do nothing with those PCs at home. Instead of letting these machines guzzle power pointlessly, you can contribute to world science and disease research, which can leave a happy fluttery feeling in your heart ;)
There are many crypto currencys out there, like CureCoin, or GridCoin, that pay you for leaving BOINC software running on your PC, so there is the added benefit of earning money, too.

I am interested, where do I start?

So you are interested, so where do you start? the Berkeley University site has a list of BOINC projects: http://boinc.berkeley.edu/wiki/Project_list

These projects range from astronomy to biology, and let you partake in helping researchers learn more. Running BOINC software on your PC is not hard, and everyone should do it, to give science that needed boost.