I had a bad accident when I was a kid riding a 'track' bike I had knocke together in the garage (think I was twelve) was going quite fast (the bike had no brakes and was single geared mega high) and I went into another lad who was coming across me. Did the flying through the air thing then the landing face first in the middle of the road thing then the standing up, spitting out my fragmented teeth thing then the shhhhhhh wierd sort of sound and not knowing who or what I am thing then fell unconcious on the road.
Thankfull a chap picked me up and took me to hospital. Apparantly the act of standing up and spitting out the shards of my teeth was exactly what I had to do to avoid inhaling them and them cutting the inside of my lungs to bits!
After that my mum insisted i ride with a helmet but I hate wearing a helmet (always have done) feels like almost all the fun of riding a bike has been taken away, you cant feel the wind in your hair, the extra weight on your head and the heat not to mention the feeling of always being concious of the fact I'm wearing a helmet.
I don't wear a helmet, I had another off last year in which I broke my arm going v.fast (spinning top gear) with a fifty/sixty mile an hour wind up my bum, tried to jump up a curb but it was the entrance to a small building site and so had like slippy clay gak on the ground. The result was a really fast slam on my left side and little knock to the bonce, finished the ride to work did a days work rode to hospital got X-rayed to see I had taken a triangular piece of the end of one of my bones in the arm and it was sitting in my elbow joint. Still there today but I haven't been able to straighten my left arm full since, going to have it operated on in a few months.
Cycling can be dangerous even fatal I guess but so can alot of things. Without wishing to appear stupid or reckless I think it is about attitude, you can ride sensibly (prefferably on a bike with brakes) and accept that accidents do happen and you might get hurt or you can wear a helmet and be more protected from head injuries.
I don't think anything of others wearing helmets but would find my enjoyment of riding seriously reduced if someone 'forced' me to wear one. I don't agree with overly protective legislation on the whole. Ride safe.