Good Gear Guide
How you can help the LHC and 12 other ways to dona...
"enables you to contribute idle time on your computer to help physicists develop and exploit particle accelerators, such as CERN's Large Hadron Collider
One application, SixTrack, generates results that are "essential for verifying the long-term stability of the high energy particles in the LHC". For CERN, volunteer computing resources are seen as useful for tasks that require lots of computing power but not so much data transfer (at the time we created this slideshow, LHC@home did not have any work for its volunteer computing force). CERN got LHC@home up and running in 2004 to celebrate the European Organization for Nuclear Research's 50th anniversary.
How you can help the LHC and 12 other ways to donate your PC's spare processing power