Y'all have already mentioned my all time favorite (Sprint's "Push-It" with the goofy dancers). And the "What does this switch do?" commercial is hilarious.
Somebody also has a cell phone commercial where these two guys are in a locker room. One of them is bragging about all the features on his cell phone. The other guy says :Well, mine has a built in security system. Try to steal my wallet" The bragging guy reaches for the guys wallet and the other guy throws his cell phone at him and hits him in the forehead. THAT IS FUNNNNYYYY!
Peace,
James