You tend to use the very specific phrase "nootropic drugs" to talk about drugs which help with productivity or creativity or some other aspect of working life. Asking whether there is evidence on nootropics, is just asking whether there are any heavily-tested nootropics. Asking anything else--to lex it out, whether "drugs that have no productivity-enhancing aspect, enhance productivity" is just playing the fool to incite extremely subjective flamewars.<p>So, let's avoid that, and just focus on nootropics. Is there evidence that they work? Depends on the drug. We have drugs (caffeine, theanine) that are in foods we've been consuming since the beginning of civilization, so we've heavily researched those and are pretty confident in what they do.<p>On the other hand, new, synthetic compounds, like modafinil, are only really created and pushed through FDA approval if there can be found some sort of therapeutic, non-nootropic purpose in their use: in modafinil's case, treating narcolepsy. This means that their use <i>as nootropics</i> is much less well-researched, and consists mainly of anecdata (however much there is) shared over the internet.<p>The best you'll find, I think, in terms of data for efficacy of various drugs, is people who have set out to do double-blind studies on themselves: <a href="http://www.gwern.net/Nootropics" rel="nofollow">http://www.gwern.net/Nootropics</a><p>After reading data-points like these, you might be convinced to try some of them on your own. But be aware that people's body-chemistries can vary widely--especially where things affecting neurochemical balance are concerned--so everyone's reactions to these will still be different. Not in a sense of a "bad trip", usually; just that some things which other people swear by might not have much of an effect on your particular chemistry. So, the best thing to do, as in most situations: first research, then experiment.