What are worthwhile extracurricular activities in college?
alexh: Debate.  Hands down.If you want public speaking skills, you will get them at debate.  When I started, I could hardly keep my sentences going the whole time.  Very recently I got into the finals of a tournament where we were judged primarily on speaking style.If you want to be able to structure arguments, as you will probably have to do when pitching a startup.  There is hardly a better way than trying a billion times, and at the same time seeing how the best in the club do it.Thinking on your feet?  You often only have the 7 minutes of your opponent's speech to come up with arguments and your own 7 minutes of refutation.  At first you are terrible, but eventually you get to the point where you are never at a loss for something to say.Coming to university with a minimal of social skills and an overload of technical skills, I have ended up getting a lot more out of debate in my first 2 terms than out of the courseload.