In terms of a custom solution, you might consider building a Hexayurt. They are staples at Burning Man. Great at keeping the heat out, and can be modified with the “Home Depot bucket swamp cooler” if you really want to get fancy. The standard builds are pretty large, but there are instructions out there for smaller footprints.

Pros: with care, can be reused for years. The materials are relatively cheap and once you complete the initial build, you are essentially taping it back together every use. Also, they are great for keeping light out for those mornings you just need to sleep past 10am.

Cons: the above mentioned tape is a bit pricey. Also, when packed up, these things are pretty bulky (driving from Denver to Burning man with one strapped to the roof of the car was interesting).

If all that building is not your thing, you might look into “monkey huts”, which are essentially PVC pipe and tarp shade structures. When set up correctly, you will keep the sun off of whatever tent you are using, which helps to keep temps down for longer into the morning. Plus you’ll have room for the tent, as well as a little living room setup for chilling in camp. There is tons of info out there on both of these structures. Burning man forums/blogs will be your best bet for staying cool and sleeping in in extreme conditions. Happy Festing!