I just took a break and found more math jokes. There are a lot of them, some of which I'd heard before, some of which I hadn't. Two of them really tickled me:

An engineer thinks that his equations are an approximation to reality.
A physicist thinks reality is an approximation to his equations.
A mathematician doesn't care.

Q: What do you get when you cross the Godfather with an economist?
A: An offer you can't understand.