We had that going into YYJ once. Just short of the piano keys the pilot abruptly pulled up, hit the gas and brought up the gear as we accelerated for a go-around. The announcement that followed was classic ... "We apologize for that ladies and gentlemen, but due to some unexpected traffic on the runway we'll go around and try that approach again. And while we're doing that, a former student at the Victoria Flying Club will be changing into a clean pair of pants." Cracked up the entire plane.