There's also been a Palo Alto hacker house for several years. I met a couple of the guys at Startup School and they seemed pretty cool. http://hackerhouse.bluwiki.com/go/Hackerhouse
It's too bad the site doesn't seem to have seen any love in a while. Last update to the main page there was over a year ago and a few of the external links seem to be broken.
Speaking as a resident, come by and visit sometime! We're a few blocks off University