As I said on Facebook, I think the best you can get is GoPro HD but they're not cheap. This is what all the motorsport people use for both exterior and interior videos.
Theres a lot of cheaper alternatives like the Veho Muvi which has some good ratings for its price and some even cheaper (10-20 quid) ones on eBay, etc that do an alright job for the money and won't matter if you break them - just buy another!