<A target="_blank" HREF=http://www.ud.com/home.htm>Intel-United Devices Cancer Research Project</A>
Basically, it's a screensaver to carry out background computing on behalf of Oxford University here in England, (and on a similar basis to the SETI project), in the search for new drugs and treatments for cancer. During the time your PC is sitting there 'doing nothing', it could be doing something beneficial.

As they put it:
To participate, you simply download a very small, no cost, non-invasive software program that works like a screensaver: it runs when your computer isn't being used, and processes research until you need your machine. Your computer never leaves your desk, and the project never interrupts your usual PC use.
There is no cost to participate and no impact on your computer use. The project software cannot detect or transfer anything on your machine but project-specific information. It just allows your computer to screen molecules that may be developed into drugs to fight cancer. Each individual computer analyzes a few molecules and then sends the results back over the Internet for further research. The goal is to enlist enough volunteers to contribute 24 million hours of computational time. This project is anticipated to be the largest computational chemistry project ever undertaken and represents a genuine hope to find a better way to fight cancer.

Set-up is very straightforward and the software seems a lot more user friendly than SETI.