What are some obnoxious practical jokes people would pull on each other in the Middle Ages?

Question

I'm writing a story with a court jester in it who doesn't know when to quit pulling practical jokes and gets himself progressively into more and more trouble.

Actually, any good practical jokes will do as long as technology isn't involved.

Somehow I don't think people's childish nature back then was that much different from today. ;-)

Answer 1

Hiding the keys to the princesses' chastity belts????  

Answer 2

uhh tying peoples shoes together?

Answer 3

same as today... putting bugs in peoples hair, beds, or pants.

Putting ice or water down peoples backs.

Putting hot spices in peoples foods or drinks.

Answer 4

He puts jalopenos in the gruel