Currently, I am not running a brake on my fixed gear/track bike. I used to, but one day I wanted to see what all the fuss about riding brakeless was all about. So I took it off. Admittedly, it scared the bejeezzuz out of me for about two days, then I got used it. Then I realized I liked the mental/psychological aspect of riding brakeless and how it affected the way I ride, in a positive way (it made me have to be more "present" when I ride, more cautiously, more aware of my surroundings, and less of a jack-ass). So I never put the brake back on. I'm sure my wife hates the idea.

However, there have been times I wished I had a brake, then again, even when I had a brake there were times when I wished I had more than one brake. So what I'm saying is: I've had "oh ****!" moments with and without a brake.