Here are some randomly selected joke topics
Threatening
Threatening letters - man asks for long sentence
Monopoly
How come there's only one Monopolies Commission?
Computers
What did one computer say to the other computer?
You've got a nice interface.
Fish
How do fish get to school?
They go by octobus.
Ghosts
What kind of mistakes do ghosts usually make?
Boo-boos.
Radio
Knock, knock.
Who's there?
Alison.
Alison who?
Alison to the radio every morning.
Elephants
What does an elephant do when he stubs his toe?
He calls the toe truck.
Elephants
How do you stop an elephant from charging?
Take away his credit cards.
Multitasking
Multitasking - screwing up several things at once.