Boredom Chasers?

yuggler asks: "Ever found yourself in a boring meeting, class or lecture? Sure! Does anyone know of something to do to make time fly? I feel that somekind of simple game, at the most requiring paper and pen would be the ultimate soultion. So, my question to you is: Does anoyone know of a game with childishly easy rules, yet with a depth that can keep the player(s) spellbound for a small eternity? An excellent example of what I'm trying to describe is the game Sprouts which only takes 30 seconds to learn, but will take a good portion of your meetings to fully understand. I am currently being tormented in a Swedish highschool, and feel in desperate need of something to get me through classes like Swedish, and Chemistry, while waiting for the programming and technology-classes."