The Berkeley Open Infrastructure for Network Computing (BOINC) is a platform for distributed computing. From the BOINC:About page:
The intent of BOINC is to make it possible for researchers to tap into the enormous processing power of personal computers around the world.
BOINC is supported by the National Science Foundation
I have been using BOINC applications since early in the SETI@home project, expanded participation through Geopense, and currently I am a BOINC alpha tester.