I share a 1 bedroom apartment with my girlfriend and dog, in a very new building that's a 20 minute walk to the office. Rent and utilities sums to $3900 for the two of us.
In a nice neighborhood in sf, you're not going going to pay less than 1600 for a room in a shared apartment, or for half of a one bedroom place.
In most markets, you can get a pretty good 1 bedroom apartment for between $900 and $1000 per month. Thus, the cost of rent in SF is around 4x the cost of rent in a normal market. You'll pay an extra $36k per year to rent in SF v. a median rental market. CA also has a much higher state tax rate than most places.
Worth keeping this in mind when you're comparing SF salaries with real-world salaries. If Google hires someone right out of school to work in SF at $100-110k, it's really like getting hired right out of school to work in a normal market at $60-70k, which isn't nearly as rare (but still pretty good for a brand new guy; in positions where I used to do hiring, we'd usually hire these somewhere between 45-55k).
I think the best way for a programmer to maximize salary is to work remotely for an SF company, getting paid an SF salary, and living in an area with a reasonable COL and (preferably) low-to-zero state income tax.
In a nice neighborhood in sf, you're not going going to pay less than 1600 for a room in a shared apartment, or for half of a one bedroom place.