This page is pretty interesting. Every ten minutes it is updated with California's real-time electricity usage. It also shows projected peak usage (e.g., today shows a big peak expected at around 6PM, which I suppose is a lot of heaters and ovens getting cranked up?), and estimated system capacity. It will be interesting to watch this going into summer.
I found that page while looking for a shop that specializes in solar/alt-energy equipment. I want to go totally renewable at Burning Man this year - it drives me a little nuts how many batteries are used and discarded at the event, and how many gasoline-powered generators hammer away night and day. There's a lot of sun on the playa!
But I'm finding it hard to find a good source. There's lots of places online, but I'm in the research phase and I'm feeling a need to inspect gear and talk to people with experience. I guess I'll just have to find a good online forum.