I have a few favorites, not all of them are funny or whatever.

1.) What's right is not always popular - what's popular is not always right.
2.) If Abercrombie said breathing isn't cool, half of the teenage population would be dead by now. (HAHA, screw A&F xD)
3.) Friendship is like peeing on yourself: everyone can see it, but only you get the warm feeling that it brings. (LOL)
4.) If practice makes perfect, but there is no such thing as perfect, what's the point in trying?
5.) Always remember you're unique, just like everyone else.
6.) Men are like bank accounts. Without a lot of money they don't generate a lot of interest.
7.) Never go to a doctor whose office plants have died.
8.) He who laughs last didn't get it.
9.) If you die in an elevator, be sure to push the Up button.
10.) Money doesn't make you happy. I now have $50 million but I was just as happy when I had $48 million.