This is an old one, and perhaps a bit over the top, but really funny!
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Three little old ladies were sitting on a park bench feeding the pigeons when a guy in a raincoat walks up and flashes them.
Two of them had a stroke. The third one's arms were too short.
What's the difference between light and hard?
You can fall asleep with a light on.
What do you have with two balls in your hand?
A man's undivided attention.