I've got a $500/month place in Chinatown, and really haven't found anything near that price with English speaking landlords. It's not to the point of missing rent or anything that dramatic yet, but I have taken on some $11/hr writing and translation work via various freelancing sites as well as some similarly priced work on a rails project. It's the surest way I see of surviving long enough to beat the chicken and egg problem of getting relevant experience.
I've been actively seeking something paid at a higher rate using platforms I've already worked on (iOS or JS/CSS), but it's going slowly. Translation is good for helping me continue to use and strengthen my 2nd (or 3rd) language. The rails work is priced as it is because I've never used rails before and I'm spending at least half the time reading docs. It's not a good long-term money-making solution, but I am learning and I'm adding something to my portfolio.
What would someone with good judgement do if their funds were running out and finding a real gig was clearly in sight but moving slowly? Missing rent would bring all kinds of pain I don't want to deal with and wreak my credit.
(the exception being for VP/COO at larger companies where a board would need to sign off)
Also, SF is expensive, and if you are staying somewhere expensive in the city while trying to find a job, you're doing it wrong. Move out to Oakland/Berkeley or even Hayward/Fremont, one of the other cheaper places and stretch out your money til you find a job... Then be prepared to look for a place to live, which is harder than finding a job in my experience... Especially if you are out of money by the time you get a job and don't have enough for the deposit of wherever you live.
Be prepared for things to take a long time, and with that in mind try to stretch out your money.