One time an idiot was at a vending machine. He would stick a quarter in, push the button, a soda would come out and he would put it on top of the machine. He did this a few more times before a man asked why he kept doing this, and he said, "Because I'm winning."
Here are some randomly selected joke topics
Students
I is a university student
Driving
Why am I the only person on earth that knows how to drive?
Signs
Sign in a restaurant window: "Eat now - Pay waiter."
Great Britain
Who is Great Britain's data compression hero?
Jack the Zipper
Undertakers
How do undertakers speak?
Gravely.
Waiters
Waiter, waiter, this food isn't fit for a pig.'
'Very good sir. I'll go and get you some that is.'
Ant
What do you call a baby ant?
An inf-ant.
Lorry
What do you call a lorry that is full of feet?
A toe truck.
Brain
If your brain was chocolate it wouldn't fill an M&M.