SpaceShare Green Travel -- carpool, community building
SpaceShare Green Travel builds ride- and room-share tools for festivals and conferences. Our sister effort Verdant Event builds complete websites for conferences with greening tools integrated.
The majority of rides posted are carpools to work and it seems to get more use in some regions than others. The most rides offered are in California, with 405 rides for the entire state, half of which are from Irvine and Redwood Shores for some mysterious reason. There are only 3 posted for San Francisco. You don't have to sign up to look for or e-mail about rideshares, and they just started a "one-time" ride message board with only a handful of posts so far [summer 2008].