Dear Tom and Ray:
I've got a 2009 Toyota Prius and recently managed to run out of gas. In my defense, the gas gauge is pretty finicky. In the past, it's allowed me to go for 50 miles after the fuel signal comes on, while this time it gave me only about 10. However, to my surprise, the car continued to run for another mile and a half on battery power, enough time for me to get to the next gas station. Did I do any harm to my battery by driving all that way without any fuel? Thanks, guys!
TOM: Nope. No harm done, Matt. But you don't want to make a habit of doing that.
RAY: Right. Once you run out of gas AND battery power, you're a sitting duck. And a dead Prius is a tempting target for SUV drivers, who may pull over, beat you up and steal your tofu sandwiches and organic hemp earth shoes.
TOM: Your batteries should recharge without any problem. But you should make a note to stop for gas within 10 miles of when the fuel light comes on. Or, better yet, stop playing Saudi Arabian roulette, and fill it up when you get to a quarter-tank.