A reader tipped us off a while back to the existence of a tool lending library in Berkeley. We were intrigued and did a little research, and lo and behold, we turned up a similar resource in San Francisco.
SF's Tool Lending Center has an extensive collection of hand tools (power tools less so) that includes implements for gardening, carpentry, concrete, plumbing, walls and floors, material handling, electrical and mechanical projects, clamps, ladders, drills, bits...we've never even heard of some of these things. (Toilet auger anyone?)
They're all listed online so you can check if they have what you need before making the shlep. Once there you need to prove you're an SF resident to get borrowing priveleges, so bring a photo ID and a utility bill. Loans are for three days.
SF's Tool Lending Center is a project of SF Clean City Coalition, which "connects resources and the neighborhood groups, merchant associations, and residents that need them." It's funded by the SF Library, and, wisely, its services include workshops and a large collection of How To reference media, in addition to the tools themselves.