Three guys are in a Cessna. The first drops a penny out the window. The 
second drops a pencil and the third a bomb. When the plane lands, the 
first guy goes to see where the penny landed. He sees a guy swearing and 
trying to get a penny out of his forehead. The second sees a girl holding 
her dog who has a pencil through his head. The third guy sees a guy 
laughing his head off. He asks, "Why are you laughing?" The guy says, "I 
was cooking on my BBQ when I farted..." "What's so funny about that?" "It 
blew my neighbor's house apart!"