Adderall
Molly Young has a worthwhile essay on n + 1's website about her use of Adderral as a performance enhancing study drug in college. It's something I tried a few times, both as she describes and as a recreational drug, back in the day but I found its effects to be pretty mild. The big plus side is that if I tried to pull all nighters based on drinking coffee or Diet Coke, I would eventually get shaky and feel a bit ill, whereas on Adderral I could really keep plugging along. It's not, however, something I really ever had great occasion to use.
Some people, though, clearly experience great effects and it does raise some questions. Do we really want to create a situation where some students may feel that they have to abuse prescription drugs to stay competitive in school? Then again, if there's a pill out there that's safe to take and helps kids learn a bunch of stuff, doesn't it seem like we should be prescribing more of it? I'd want to know more about what the real medical affects of taking the stuff before I made any kind of judgment. I will say that I was a bit shocked to hear about some of the younger faculty using it to help get their work done, but even though at the moment Adderral seems to mainly be a vice of college students there's no particular reason it couldn't be useful (in good ways or bad) for a much wider range of people.