Just watched an interesting commentary regarding Hybrids and a collision.

Hybrids rely on high voltage power to run their electric motor. Around 500V. This means high voltage wires run through the door (at least right now) so emergency crews are being told not to cut through the doors, but to remove the roof.

So, those high voltage batteries could be very dangerous in a collision if a wire gets cut and shorts out on the body and gets grounded through a passenger.