I went to Burning Man in 2000, mostly because a bunch of my friends were going, and I figured it was one of those things that everybody should experience once. It was an interesting experience. I think the best part from my perspective was getting there early before the party started (I was there nine days), and watching the city grow up around me. I was helping to set up the central cafe, and each morning as I wandered from our campsite to center camp, there would be more and more structures around; landmarks would change daily. It was fascinating to watch this city of 30,000 people appear around me.
Anyway, what reminded me of it was reading an article in the Chronicle this morning, discussing the planning that is necessary to make a town work. Even a town as anarchic and free-spirited as Black Rock City needs rules. They have roads, they have a public works department, and they try to situate similar camps together. Good article.