I did as a kid but haven't thought about it as an adult. However.....

....I accidentally forgot my helmet a couple of months ago and continued to ride that day without it. Have to tell you it felt great! I rode a LOT as a kid and we did all kinds of crazy stuff. I never hit my head nor did I know anyone who did. I'm not recommending anyone not ride with a helmet...but it's a wonder we made it to adulthood. Oh, and I also talk to farm animals when I ride by. Guess I'm regressing.