Developer Will Henderson recently unveiled a beta of MultiClutch
"In honor of the new multitouch-equipped Macbook Pros, I’m going to make [MultiClutch] public in hopes that others will find it useful," said Henderson on his blog. "Want swipes to change tabs in Safari? Done. The same in iChat? Done. Want zoom-in to open emails in Mail, zoom-out to close windows in every app, and a swipe down to bring up Quicksilver? Done done done."