SETI@home is a scientific experiment that will harness the power of
hundreds of thousands of Internet-connected computers in the Search for
Extraterrestrial Intelligence (SETI).  You can participate by running a
program that downloads and analyzes radio telescope data.  There's a
small but captivating possibility that your computer will detect the
faint murmur of a civilization beyond Earth.

WWW: http://setiathome.ssl.berkeley.edu/