Moving to San Francisco on New Year's Eve and looking for decent, cheap housing.

I've been looking at Craigslist, but I wanted to put out a call to the SF reddit community as well.

I currently live in Seattle and because of my job schedules, I can't get down to SF before I move to scope out the housing situation, but I'd really like to have a place to move in when I arrive in the city. Does anyone know of any decent, cheap places to live that are available at the end of December/January 1st?

I'm used to house shares, but I would prefer not to share a room. I can afford to spend about $500 a month on housing, plus a bit extra for utilities if they are not included.

Anyway, thanks for reading. I'd be grateful for any suggestions you might have.