I recently started taking piracetam, a safe and unregulated (in the US) nootropic drug that improves memory. The effect (at a dose of 1.5g/day) was much stronger than I anticipated; I expected the difference to be small enough to leave me wondering whether it was mere placebo effect, but it has actually made a very noticeable difference in the amount of detail that gets committed to my long-term memory.

It is also very cheap, especially if you buy it as a bulk powder. Note that when taking piracetam, you also need to take something with choline in it. I bought piracetam and choline citrate as bulk powders, along with a bag of empty gelatin capsules and a scale. (Both piracetam and choline citrate taste extremely vile, so the gel caps are necessary. Assembling your own capsules is not hard, and can be done at a rate of approximately 10/minute with a tolerance of +/- 10% once you get the hang of it.)

I strongly recommend that anyone who has not tried piracetam stop procrastinating and order some. Yes, people have done placebo-controlled studies. No, there are not any rare but dangerous side effects. Taking piracetam is an unambiguous win if you want to learn and remember things.