Barry Bonds, voting, and playing hooky
The Freakonomics guys blogged on voting last week. Basically, they said you don't find many economists who vote, because the chance of your one vote determining the outcome of the election is slim to none. I had the a similar thought regarding class attendance while in lecture today. It's painfully apparent in high school, but it's even true in college. In many cases due to lowering standards and our current grading system, missing one day of class almost never has a significant effect.
If you approach each class as independent of the other classes (depending on the material, this can sometimes be a valid assumption), gaming theory* would tell me not to any classes (except tests and quizzes). Extra credit or pop-quiz potentials are a start towards giving every class an increased payback; attendance grades clearly do the trick (and students come to class for the wrong reasons). Yes, the good classes are the classes you go to because, "if you miss one, you're screwed."
Rationally, voting is a waste of time, as is going to many lectures... but superrationally, I should go to all my classes and hit the polls every time.
*The problem and implications of playing hooky from lecture or the polls bears a striking resemblance to the traveler's dilemma (similar to the prisoner's dilemma).