that's when you blow past em'...
that said I commute on a fixed gear lately. 49x15 gearing and I still fly past the hipsters on the uphills now that they've come back out from their winter hibernation.
You can definitely gain some serious strength from riding fixed. With me the 49x15 gearing was way too steep at first.. but I kinda like it now because it really pushes me harder on climbs which I feel translates to when I'm on the road bike.