Ask HN: Best networking venues in SF to meet programmers

I'm an energy and environmental policy wonk in SF with a non-CS engineering background. I'm working on a venture and am trying to build a stronger network of CS folks. Here's my shtik:

I go to networking events, talk it up, occasionally make public pitches, and often meet some great people, the best of whom all have their own gigs. However, over time I start recognizing the same faces and begin feeling like I'm fishing in the wrong pond. I wonder if there are other good meetup venues not on my radar.

Aside from major conferences - often too costly for a mooch in my shoes - can you help add to my list of regular SF Bay area tech-focused networking events:

SF Beta SF New Tech SDForum events Svase events TiE events Interest groups on Meetup (e.g. Python, Rails groups) Open Hacker House in the Mission Dist. (which just came to my attention) and...