Joke: Knock knock!
Who's there?
Doorbell repairman!
Doorbell repairman who?
Ding dong! My work here is done.

Joke: What's the best way to throw a party in space?

Joke: Knock knock!
Who's there?
Aldehyde!
Aldehyde who?
...
Must have been a leaving group.

Joke: Why did the bowling pins stop working?

Joke: Math guy #1: It's ironic.
Math guy #2: What is?
Math guy #1: You can't spell tautology without spelling tautology.

Joke: Two sisters, one is blonde and one is brunette, are trying to start a farm. The brunette sister finds a prized bull in the classified and leaves to check it out. She tells the blonde that she will contact her to come haul the bull back to the farm if she decides to buy it.

The brunette goes to the farm and decides to buy it. The farmer tells her that the bull will cost exactly $599, no less. So she buys the bull and heads to town to contact her sister. The only person she can find to help her is a telegraph operator.

The operator tells her "It costs 99 cents per word, what would you like to send?"

The brunette replies "Well I only have $1 left." She thinks for a while and tells the operator she wants to send the word 'comfortable.'

The operator asks "How will she know you bought the bull and want her to bring the haul from the word comfortable?"

The blonde replies "She's a slow reader."