The LA Times has a review of the wetware enhancers -- cog drugs for the able minded. I didn't realize Provigil had gained a reputation for enhancing cognition; caffeine, of course, has been known to do that for some time.
The review omits nicotine, a curious drug which is both calming and alerting (and hence beloved in wartime).
I suspect some of these will have quite hideous side-effects. I'm sure I'll end up on one or more though -- especially if the alternative is bagging groceries.