Why did the dishonest man keep his word? (no one would take it)
What fruit grows on telegraph poles? (electric currents)
Why was the rock emotional? (because it was easily moved)
When is a tooth like a plot of land? (when it's an acre)
What letters are never tired? (N R G)
Why is a watch like a river? (it doesn't run long without winding)
What has only one foot? (a leg)
When is a clock angry? (when it strikes one)
Why is it rude to whisper? (because it's not aloud)
What's the principal part of a horse? (the mane part)
Why do people who write books look strange? (tales come out of their heads)

Have any you'd like to share?