I haven't worn a helmet since I was 14 (age cutoff for the state helmet law). I have never fallen off a bicycle since I first started learning how to ride a 2-wheeler and even then I never hit my head. However with my recent thoughts of participating in organized tours, I learned they all require helmets worn by every participant, so I'm headed to my LBS to pick one out. I'm sure when I start wearing it, when required, it'll probably come natural that I wear it whenever I'm on the bike.