I booked and received a Prius for two weeks last month out of SFO. It was horribly expensive (450/week). Even though I put 2,000 miles on the thing I knew I wouldn't end up saving on gas. I got it for the novelty factor. I always wanted to buy a Prius in the past, but couldn't justify spending all the extra cash (I ended up with a Honda Fit). So renting a Prius got that out of my system.

Plus it was fun to drive from one side of Blue Lake, CA to the other on just the battery!

(Regular gas in Humboldt County, CA last month was $4.79 gallon too. Ouch!)