A good question was posed the other day about how to get rid of your old mattress. SF Recycling considers mattresses bulky items, which they will pick up for free once a year for apartment-dwellers and twice a year for those in a house or flat. If you've already used up your bulky item pick-up for the year, SF Recycling will pick it up for a fee (call for prices), or you can drop it off for $8 per mattress, plus a $21 disposal fee.
As mentioned previously, SFEnvironment.org has a great list of additional resources. You can drop off your mattress for free at Raphael House (call ahead for times). (Update 2/9/16: Raphael House no longer accepts mattresses for recycling, Director of Facilities & Hospitality Jerry Maynard says. Please don't try to drop them off there!) BedBusters will come pick it up for a charge based on mattress size. Estates Mattress Company in Oakland will recycle single- and full-sized mattress drop-offs for $10 per mattress. Additionally, there is EcoHaul, but it sounds like you'd need a truck-full of items to make it worth the price (call/email for prices).
On a side note, leave it to Yelp to have a review page for Crap That People Leave On The Street.