I think the real solution is this: 
I'm not that irrational. As for hot-wiring the car as coffeesp00ns suggests -- yes, maybe (can you hotwire a Prius?) -- and if they want to work that hard, fine. I just don't want to make it easy for them.
I found a discussion page on this question: http://priuschat.com/threads/hot-wiring-a-prius.3353/In a nutshell - the only way this car is leaving without you is if it's towed or if someone steals your key (or if a dealer/mechanic secretly programs an additional key while working on yours).
Prii are cool but I can't stand to drive them really and the 2006 model had terrible noise canceling on the highway. Took one around Yellowstone Nat'l Park where there aren't many gas stations and it was incredibly helpful, though. I'd like to try a new one sometime.