Just stumbled on Grokker

Their product grokker works on top of a search engine to present search results in a graphical multi-layer fashion instead of usual long list of links.

Interesting UI innovation that moves users away from long listbox paradigm. Also interesting is the way they classify search results to divide entire result set into logical subsets.

The Register : "SETI@home crew is dabbling with Sun's JXTA peer-to-peer protocols for future versions of BOINC. "
5M SETI@home users on JXTA network would be a good test!