friend's couch
shack up with an older gay man
If you are talking SF, there are some other options:
www.sfofficelofts.com - a friend of mine (an artist, not in software) rents one of these for $725 a month. It is a huge loft. The downside - you share a bathroom with everyone else on the floor, like a college dorm. And, the building is conveniently located between a porno theatre and an alley full of meth tweakers.
The usual option is to find a share on craig's list. http://sfbay.craigslist.org/roo
Oakland Chinatown is one of those rare places where some of the eateries are open 363 out of the 365 days.
I haven't tried them out yet but plan to when I move to Cambridge in a few weeks. Seems like a good way to save money if public transportation gets you most places but you still need a car.
Also check out places near SF State, shaking up with a student can be a good way to go.
https://wifi.google.com/support/bin/answer.py?answer=44022