I took 1.5mg of melatonin, and went to bed at ~1:30AM; I woke up around 6:30, took a modafinil pill/200mg, and felt pretty reasonable. By noon my mind started to feel a bit fuzzy, and lunch didn’t make much of it go away. I’ve been looking at studies, and users seem to degrade after 30 hours; I started on mid-Thursday, so call that 10 hours, then 24 (Friday), 24 (Saturday), and 14 (Sunday), totaling 72hrs with <20hrs sleep; this might be equivalent to 52hrs with no sleep, and Wikipedia writes:
Microdosing involves ingesting small amounts of psychedelics to induce a very subtle physical and mental effect accompanied by a very noticeable, overall positive, health effect. When you take a microdose of a psychedelic, it is typically referred to as a sub-perceptual dose. A sub-perceptual dose will not have a major impact on your ability to function normally, but the effect will definitely be present in your mood and behavior. The microdose of a particular psychedelic is correlated to the lowest dose that will produce a noticeable effect, which is also known as the threshold dose. Since the goal is not to get a hallucinogenic effect, a microdose can be well below the psychedelics threshold dose. By integrating the correct doses of psychedelics into your weekly routine, you can achieve higher creativity levels, more energy, improved mood, increased focus, and better relational skills. There is a growing body of research that shows microdosing to improve depression, anxiety, PTSD, and emotional imbalance, help with alcohol and tobacco addiction, and decrease ADD and ADHD behaviors.
The fish oil can be considered a free sunk cost: I would take it in the absence of an experiment. The empty pill capsules could be used for something else, so we’ll put the 500 at $5. Filling 500 capsules with fish and olive oil will be messy and take an hour. Taking them regularly can be added to my habitual morning routine for vitamin D and the lithium experiment, so that is close to free but we’ll call it an hour over the 250 days. Recording mood/productivity is also free a sunk cost as it’s necessary for the other experiments; but recording dual n-back scores is more expensive: each round is ~2 minutes and one wants >=5, so each block will cost >10 minutes, so 18 tests will be >180 minutes or >3 hours. So >5 hours. Total: 5 + (>5 \times 7.25) = >41.
But while some studies have found short-term benefits, Doraiswamy says there is no evidence that what are commonly known as smart drugs — of any type — improve thinking or productivity over the long run. “There’s a sizable demand, but the hype around efficacy far exceeds available evidence,” notes Doraiswamy, adding that, for healthy young people such as Silicon Valley go-getters, “it’s a zero-sum game. That’s because when you up one circuit in the brain, you’re probably impairing another system.”
Nootropics may seem attractive to anyone who wants to try to improve their cognitive function and is willing to purchase powders, pills and other forms of these natural and synthetic supplements. Nootropic users have their own terminology, referring to measured combinations of nootropics and vitamins and minerals as “stacks.” For instance, Danger and Play, a site for active people, features a stack for beginners.[5] The recipe includes 1600 mg of the piracetam along with recommended dosages of supplements such as ALCAR, rhodiola and magnesium. There are recipes for morning, afternoon and night, thus providing daylong guidance on how to most effectively stack for more energy, greater concentration, and improved information retention. The stack tip specifically states that the ingredients are not addictive, especially if taken in strict accordance with the recipe.

Tempted to skip breakfast? Studies have found that eating breakfast may improve short-term memory and attention. Students who eat it tend to perform better than those who don’t. Foods at the top of researchers' brain-fuel list include high-fiber whole grains, dairy, and fruits. Just don't overeat; researchers also found high-calorie breakfasts appear to hinder concentration.
Whether you want to optimise your nutrition during exam season or simply want to stay sharp in your next work meeting, paying attention to your diet can really pay off. Although there is no single 'brain food' that can protect against age-related disorders such as Alzheimers' or dementia, and there are many other medical conditions that can affect the brain, paying attention to what you eat gives you the best chance of getting all the nutrients you need for cognitive health.
Systematic reviews and meta-analyses of clinical human research using low doses of certain central nervous system stimulants found enhanced cognition in healthy people.[21][22][23] In particular, the classes of stimulants that demonstrate cognition-enhancing effects in humans act as direct agonists or indirect agonists of dopamine receptor D1, adrenoceptor A2, or both types of receptor in the prefrontal cortex.[21][22][24][25] Relatively high doses of stimulants cause cognitive deficits.[24][25]