One of my favorite gags on the Simpsons is when there are akward silences.
The new German owners ask Homer that he must have some great ideas for the future. Homers responds enthusiastically, "I SURE DO!!!!" then, SILENCE.
When introducing the world premier of the Party Posse, The girl on TV is shouting ya! alright!!! then stands still, waiting for the camera to go off in silence. Realizing that she is still on, she begins shouting again.
When Lisa is finsished having the story of her "true" love told, the fortune teller is engulfed by a clowd of smoke, as if she were disappearing. When the cloud dissappears, the woman remains (of course) and stares at Lisa in silence.
What else?