I trackstand with my left forward, since my wheel is usually cocked around 45 degrees to the left due to the ridiculously crowned streets in Denver. Before I recently changed my gearing, I had sometimes been trackstanding with my left almost at 12 and my right at 6. Go figure. I can skip w/either foot forward pretty comfortably, but always skid with my right forward.
I have been trying to teach myself to ride backwards lately, and have a feeling that the balance shift needed for making it through more than one pedal rotation is going to diminish my dominant foot tendencies. Plus I'll have a circus trick to fall back on if I lose my job.