Buy something cheap-ass at WalMart and keep it in a big Zip-Loc bag.

I recently shot a beach wedding and everyone warned me that although camera-wraps and slicks do a decent job protecting against rain, sand is a totally different animal (since it comes in from the bottom, etc).

On my day, the winds were still enough and the sand not fine enough to be a problem -- all was OK (although the tripod legs had seen better days).

- For < $500, you'll have to get a consumer cam
- I like my Canon Optura consumer -- any camera that allows you to slow the shutter speed will do better at night. Sony's "Night Shots" I've found are amazing in pitch-black, but your image has an erie green cast to it (which can be removed in post-prod, or by simply turning on the "Sepia" or B&W effect.

Whatever you get, WRAP IT GOOD at Burning Man -- I hear the playa dust is Super-Fine and it *will* get into your camera (and warrantees probably won't cover sand damage :-)
- sealed in a ziplock bag
- wrapped with a garbage bag and rubber bands
- i've heard of some pros wrapping the whole camera with DUCT TAPE (I don't know how they change tapes/film) when shooting in the desert

Just my 2 cents...
:-) Rob

P.S. If your camera gets lost while on the road (including Burning Man), most homeowners and renters insurance policies will cover replacement of the unit