What seemed to happen is that whatever flew up under my car knocked something, breaking part of my hood latch, then fell back down and jumped into my wheel where it broke the caliper, knocking off a bolt, and the caliper fell into the wheel, getting mutilated in the process, turning itself into a big chunk of wheel-stopping metal blob.
Anyway, total cost for towing, labor, and new caliper: $179. Not bad. I'll need some minor body work when I get home, too, but insurance is covering almost all of it because as I said earlier, not taking the rental car option means that money comes off my deductible.
Now that I have my car, it's actually kinda frustrating: driving is way slower than biking with all this traffic. But my car has my mp3 player, so it's a trade-off. I figure I'll drive today, since I'm a little sore from the last two days, but I'll probably be biking the next couple days because it's so nice out.