Theoretical Computer Science Cheat Sheet

This is a nice cheat sheet on what they call "Theoretical Computer Science Cheat Sheet", http://www.tug.org/texshowcase/cheat.pdf. I have not heard of half of them--some we touched in the algo class. Once thing I learned there was, representing simple phenomenon---like the expected number of throws before getting N heads in a coin toss---very often lead to very complex math . So once in a while, when we--system guys--try to explain things we saw, those things could come handy.