"We're entering an era when we will be able to scan billions of channels," said project chief scientist Dan Werthimer. "Arecibo is now optimized for this kind of search, so if there are signals out there, we or our volunteers will find them."

So far, SETI has been dependent on five million volunteers networking their computers into the world's largest cluster supercomputer--comprised at any one time of as many as 320,000 computers at 170,000 users' homes. But with 500-times more data streaming in, according to project scientist Eric Korpela, SETI is trumpeting its need for more users to offer their computers for use in the supercomputer cluster after hours by signing up with SETI@Home.

There, you can enlist your computer into the Berkeley Open Infrastructure for Network Computing (BOINC), which was developed for SETI@home by its director, David Anderson. More than 42 separate projects are coordinated by BOINC to use the computing power of SETI's radio telescope to detect intelligent life elsewhere in the universe. Until now, there have been enough volunteers, but with the same amount of data as is housed in the U.S. Library of Congress streaming in yearly--100 terabytes per year (about 300 gigabytes per day)--SETI needs more volunteers.

BOINC was one of the first clusters of volunteer computers to harness unused time on personal computers worldwide. Since its inception in 1992, several other distributed computing projects have sprung up, such as folding@home, which unravels the three-dimensional tangle of proteins, and cosmology@home, which models other possible universes.

The Arecibo dish is 1000 feet in diameter, filling a valley in Puerto Rico. It is owned by the National Astronomy and Ionosphere Center and operated by Cornell University with funds from the National Science Foundation. SETI is supported financially by NSF, the Planetary Society, Sun Microsystems, and individual donations from its volunteers.