If they work, we'd put them in the "free" section on Craigslist -- we've done that with quite a few things. We haven't tried Freecycle, but we know there are readers who have.
If they don't, the first one that came to mind was GreenCitizen.
There's also the Alameda County Computer Resource Center and the Computer Recycling Center" (neither are just for computers).
Originally posted by Leslie on AT:SF.