Math Capella

I was first sent this back in 2005 at which point I didn't really know what it was all about. Now that I'm finally in the position where I actually get the jokes, I figure I can share it with you without loss of face. Behold the Klein Four: an A Capella group composed of mathematics students at Northwestern University near Chicago. They're clearly differential geometers/mathematical physicists. It's what all the cool kids do.

This simply cannot be beaten for sheer density of maths puns. Buy T-shirts here.