My boss came to me at lunch, "Where the hell have you been? I've been trying to find you all morning!"

I shrugged and said, "Good employees are hard to find!"

What is muffins spelled backwards?

Exactly what you do when you take them out the oven.

Shop assistant: How about this one?

Psychic: That shirt is too small.

Shop assistant: You didn't even try it on?

Psychic: I'm a medium.

Which is heavier: a litre of water or a litre of butane?

The water.

No matter how much you have, butane will always be a lighter fluid.