If you like the desert, you may want to look into taking a Joshua Tree jeep tour. Looks like a fun experience, as long as you don't wait to to take this tour anytime during the summer! I've actually never been to Joshua Tree (I know, I'm lame!), but if and when I go, I wouldn't mind taking one of these jeep tours.
There are various companies that offer the tour and the average cost is about $125 per person for a 4-5 hour tour.
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