I'm late on this, but most fixie riders I've seen had to have the jedi skills, esp the brakeless ones....

And agreed with everyone else on the cog/lockring. I recommend the rotafix method to make sure the cog is tight, then hit the lockring. If you have a brake, go out and pedal really hard without backpedaling, then take your feet off and stop with the brake. Hit the lockring after that.