I have recently discovered (out of necessity) that my pakiT is actually quite small and you can stand over it on a crowded Bart train. The trick is to quick fold, then grab and rotate it vertically like a unicycle. It sits fine on the front tire, and actually rolls well like that, too. Stand over with the saddle in front of your crotch and hold the saddle. You can rubber-band the front brake lever to prevent rolling if your train lurches a lot.