Don't expect me to pay your bills while you're laid up after being hit by a car while biking in traffic. If you don't think enough of yourself to ride in a car while in traffic, why should I.

And people who pretend that helmets will help prevent serious injury if you are involved in an accident with a car or in an accident while your bike is moving at (or who even think that helmets can prevent concussion) are either willfully ignorant or illiterate.

But if you are going to wear a helmet, I recommend the bowler helmet:

From here: http://www.bobbinonline.co.uk/Mr-Ben-Bowler-Helmet