Your mileage will vary. There are so many parameters and interactions in the brain that any of them could be the bottleneck or responsible pathway, and one could fall prey to the common U-shaped dose-response curve (eg. Yerkes-Dodson law; see also Chemistry of the adaptive mind & de Jongh et al 2007) which may imply that the smartest are those who benefit least23 but ultimately they all cash out in a very few subjective assessments like energetic or motivated, with even apparently precise descriptions like working memory or verbal fluency not telling you much about what the nootropic actually did. It’s tempting to list the nootropics that worked for you and tell everyone to go use them, but that is merely generalizing from one example (and the more nootropics - or meditation styles, or self-help books, or getting things done systems - you try, the stronger the temptation is to evangelize). The best you can do is read all the testimonials and studies and use that to prioritize your list of nootropics to try. You don’t know in advance which ones will pay off and which will be wasted. You can’t know in advance. And wasted some must be; to coin a Umeshism: if all your experiments work, you’re just fooling yourself. (And the corollary - if someone else’s experiments always work, they’re not telling you everything.)

On the plus side: - I noticed the less-fatigue thing to a greater extent, getting out of my classes much less tired than usual. (Caveat: my sleep schedule recently changed for the saner, so it’s possible that’s responsible. I think it’s more the piracetam+choline, though.) - One thing I wasn’t expecting was a decrease in my appetite - nobody had mentioned that in their reports.I don’t like being bothered by my appetite (I know how to eat fine without it reminding me), so I count this as a plus. - Fidgeting was reduced further
With subtle effects, we need a lot of data, so we want at least half a year (6 blocks) or better yet, a year (12 blocks); this requires 180 actives and 180 placebos. This is easily covered by $11 for Doctor’s Best Best Lithium Orotate (5mg), 200-Count (more precisely, Lithium 5mg (from 125mg of lithium orotate)) and $14 for 1000x1g empty capsules (purchased February 2012). For convenience I settled on 168 lithium & 168 placebos (7 pill-machine batches, 14 batches total); I can use them in 24 paired blocks of 7-days/1-week each (48 total blocks/48 weeks). The lithium expiration date is October 2014, so that is not a problem

Bacopa Monnieri:  Also known as “waterhyssop,” this herb grows in wetlands around the world.  It has a long history of use in Ayurvedic medicine.  It is a powerful antioxidant which had demonstrated protective effects on cells.  It also has anti-inflammatory properties.  Inflammation is believed to play a major role in the development of dementia.  Additionally, this herb boosts blood flow to the brain and activates choline acetyltransferase, a key enzyme which is necessary to synthesize the neurotransmitter cetylcholine.
Brain Awake is produced by Irwin Naturals. The ingredients are natural and include some key ingredients. However, it also contained several other inactive ingredients that raised some concerns - namely, beeswax and silicone dioxide. We were not sure why these ingredients are included, and could not find any real explanation as to why they are contained within this product. That said, when we tested the ingredients in this product, they were as reported on the bottle.
To make things more interesting, I think I would like to try randomizing different dosages as well: 12mg, 24mg, and 36mg (1-3 pills); on 5 May 2014, because I wanted to finish up the experiment earlier, I decided to add 2 larger doses of 48 & 60mg (4-5 pills) as options. Then I can include the previous pilot study as 10mg doses, and regress over dose amount.
Be patient.  Even though you may notice some improvements right away (sometimes within the first day), you should give your brain supplement at least several months to work.  The positive effects are cumulative, and most people do not max out their brain potential on a supplement until they have used it for at least 90 days.  That is when the really dramatic effects start kicking in!

Piracetam is used to increase memory, learning, and concentration. It is not reported to be toxic even at high doses, but healthy people are reported to not get that much of a boost from it, and it is understood to be most effective for older people. It’s been found to reduce the chances of a breath-holding spell in children, enhance cellular membrane fluidity, and prevent blood clotting on par with aspirin.
Forums including have more than 140,000 subscribers discussing products with names like Orange Brainwash and GodMode. Nootropics are blends of ingredients touted as a low-risk way to enhance learning, memory, motivation, and even serenity. These ingredients range from herbs such as water hyssop (Bacopa monnieri) and arctic root to chemicals such as vinpocetine.
Dark chocolate. Let's end with the good stuff. Dark chocolate has powerful antioxidant properties, contains several natural stimulants, including caffeine, which enhance focus and concentration, and stimulates the production of endorphins, which helps improve mood. One-half ounce to 1 ounce a day will provide all the benefits you need, says Kulze. This is one "superfood" where more is not better. "You have to do this one in moderation," says Kulze.

A total of 330 randomly selected Saudi adolescents were included. Anthropometrics were recorded and fasting blood samples were analyzed for routine analysis of fasting glucose, lipid levels, calcium, albumin and phosphorous. Frequency of coffee and tea intake was noted. 25-hydroxyvitamin D levels were measured using enzyme-linked immunosorbent assays…Vitamin D levels were significantly highest among those consuming 9-12 cups of tea/week in all subjects (p-value 0.009) independent of age, gender, BMI, physical activity and sun exposure.
Took pill around 6 PM; I had a very long drive to and from an airport ahead of me, ideal for Adderall. In case it was Adderall, I chewed up the pill - by making it absorb faster, more of the effect would be there when I needed it, during driving, and not lingering in my system past midnight. Was it? I didn’t notice any change in my pulse, I yawned several times on the way back, my conversation was not more voluminous than usual. I did stay up later than usual, but that’s fully explained by walking to get ice cream. All in all, my best guess was that the pill was placebo, and I feel fairly confident but not hugely confident that it was placebo. I’d give it ~70%. And checking the next morning… I was right! Finally.
NGF may sound intriguing, but the price is a dealbreaker: at suggested doses of 1-100μg (NGF dosing in humans for benefits is, shall we say, not an exact science), and a cost from sketchy suppliers of $1210/100μg/$470/500μg/$750/1000μg/$1000/1000μg/$1030/1000μg/$235/20μg. (Levi-Montalcini was presumably able to divert some of her lab’s production.) A year’s supply then would be comically expensive: at the lowest doses of 1-10μg using the cheapest sellers (for something one is dumping into one’s eyes?), it could cost anywhere up to $10,000.

Wild salmon. Deep-water fish, such as salmon, are rich in omega-3 essential fatty acids, which are essential for brain function, says Kulze. Both she and Pratt recommend wild salmon for its "cleanliness" and the fact that it is in plentiful supply. Omega-3s also contain anti-inflammatory substances. Other oily fish that provide the benefits of omega-3s are sardines and herring, says Kulze; she recommends a 4-ounce serving, two to three times a week.

Googling, you sometimes see correlational studies like Intake of Flavonoid-Rich Wine, Tea, and Chocolate by Elderly Men and Women Is Associated with Better Cognitive Test Performance; in this one, the correlated performance increase from eating chocolate was generally fairly modest (say, <10%), and the maximum effects were at 10g/day of what was probably milk chocolate, which generally has 10-40% chocolate liquor in it, suggesting any experiment use 1-4g. More interesting is the blind RCT experiment Consumption of cocoa flavanols results in acute improvements in mood and cognitive performance during sustained mental effort11, which found improvements at ~1g; the most dramatic improvement of the 4 tasks (on the Threes correct) saw a difference of 2 to 6 at the end of the hour of testing, while several of the other tests converged by the end or saw the controls winning (Sevens correct). Crews et al 2008 found no cognitive benefit, and an fMRI experiment found the change in brain oxygen levels it wanted but no improvement to reaction times.
If I stop tonight and do nothing Monday (and I sleep the normal eight hours and do not pay any penalty), then that’ll be 4 out of 5 days on modafinil, each saving 3 or 4 hours. Each day took one pill which cost me $1.20, but each pill saved let’s call it 3.5 hours; if I value my time at minimum wage, or 7.25/hr (federal minimum wage), then that 3.5 hours is worth $25.37, which is much more than $1.20, ~21x more.
As discussed in my iodine essay (FDA adverse events), iodine is a powerful health intervention as it eliminates cretinism and improves average IQ by a shocking magnitude. If this effect were possible for non-fetuses in general, it would be the best nootropic ever discovered, and so I looked at it very closely. Unfortunately, after going through ~20 experiments looking for ones which intervened with iodine post-birth and took measures of cognitive function, my meta-analysis concludes that: the effect is small and driven mostly by one outlier study. Once you are born, it’s too late. But the results could be wrong, and iodine might be cheap enough to take anyway, or take for non-IQ reasons. (This possibility was further weakened for me by an August 2013 blood test of TSH which put me at 3.71 uIU/ml, comfortably within the reference range of 0.27-4.20.)
A picture is worth a thousand words, particularly in this case where there seems to be temporal effects, different trends for the conditions, and general confusion. So, I drag up 2.5 years of MP data (for context), plot all the data, color by magnesium/non-magnesium, and fit different LOESS lines to each as a sort of smoothed average (since categorical data is hard to interpret as a bunch of dots), which yields:

A key ingredient of Noehr’s chemical “stack” is a stronger racetam called Phenylpiracetam. He adds a handful of other compounds considered to be mild cognitive enhancers. One supplement, L-theanine, a natural constituent in green tea, is claimed to neutralise the jittery side-effects of caffeine. Another supplement, choline, is said to be important for experiencing the full effects of racetams. Each nootropic is distinct and there can be a lot of variation in effect from person to person, says Lawler. Users semi-annonymously compare stacks and get advice from forums on sites such as Reddit. Noehr, who buys his powder in bulk and makes his own capsules, has been tweaking chemicals and quantities for about five years accumulating more than two dozens of jars of substances along the way. He says he meticulously researches anything he tries, buys only from trusted suppliers and even blind-tests the effects (he gets his fiancée to hand him either a real or inactive capsule).

As with any thesis, there are exceptions to this general practice. For example, theanine for dogs is sold under the brand Anxitane is sold at almost a dollar a pill, and apparently a month’s supply costs $50+ vs $13 for human-branded theanine; on the other hand, this thesis predicts downgrading if the market priced pet versions higher than human versions, and that Reddit poster appears to be doing just that with her dog.↩

Coconut oil was recommended by Pontus Granström on the Dual N-Back mailing list for boosting energy & mental clarity. It is fairly cheap (~$13 for 30 ounces) and tastes surprisingly good; it has a very bad reputation in some parts, but seems to be in the middle of a rehabilitation. Seth Robert’s Buttermind experiment found no mental benefits to coconut oil (and benefits to eating butter), but I wonder.
Brain consumption can result in contracting fatal transmissible spongiform encephalopathies such as Variant Creutzfeldt–Jakob disease and other prion diseases in humans and mad cow disease in cattle.[10] Another prion disease called kuru has been traced to a funerary ritual among the Fore people of Papua New Guinea in which those close to the dead would eat the brain of the deceased to create a sense of immortality.[11]

The desire to improve cognitive functioning has probably existed since the dawn of human consciousness. Throughout our evolution, increased mental agility has been associated with fitness and improved odds of survival and success. Although concoctions to stimulate brainpower have existed in Chinese and Indian medicine for hundreds of years, Western nootropics were not developed until 1964.
Second, users are concerned with the possibility of withdrawal if they stop taking the nootropics. They worry that if they stop taking nootropics they won’t be as smart as when they were taking nootropics, and will need to continue taking them to function. Some users report feeling a slight brain fog when discontinuing nootropics, but that isn’t a sign of regression.