What Formula Would You Tattoo?

My_Skin_As_A_Cheatsheet asks this potentially painful question: "I have a friend/colleague who is planning on getting a tattoo in the next month or so. She has decided that this tattoo will be a mathematical or statistical formula, and has been scouring the web and books in recent weeks looking for a cool formula to put on her upper back/shoulder. If you could tattoo a single formula, axiom, etc. (from math, statistics, or any other similar field) on you, what would it be and why? Are there any you think are particularly profound or important? Cool symbols are a plus." Do you have a formula that means so much to you that you would get it tattoed onto your skin? If so, please share it with us. Please try to do you best in HTML (and I wish there was MathML support in something other than Mozilla...of course, Slashdot won't accept those tags anyways...yet!).

Comments

My personal favorite..

[cmowire]

I would tattoo the following:

Integral(E^x) = f(u^n)
Which becomes, when you look at it,
Sex = Fun

That would be my suggestion. ;)