There's Hackers and Founders, that I organize. We're based on the penninsula, but we're going to start having meetups in SF every 4-6 weeks. http://www.hackersandfounders.com
yes, we will be doing a meetup during sxsw on Mon 15th march at submerged from 5 - 7. pg will be at that one also as he's on a sxsw panel. will send out more details soon.