As far as motorcycle helmets go, I was told by an old biker once that him and his buddies didn't believe in wearing a helmet. Reason being, is that if they were involved in a crash of any significance, they would rather be dead men on their bikes rather than a vegetable for the rest of their life not able to ride again.
Hardcore bikers, yes. I understand his point as it makes perfectly good sense to me. However, I was glad to be wearing a full carbon fiber helmet the day a guy made a left in front of me while i was cruising at about 60. Even with the helmet I fractured my c1 vertebrae to 2mm from the breaking point, suffered some nerve damage and burnt my leg up pretty bad. I am glad to still be alive and thank the helmet for it, but still I understand that old bikers point.