I tried adderall for concentration at a standard therapeutic dose, but the jitters and palpitations.
These days, I just use mirtazapine (depression) and flonase (sleep apnea) and occasional caffeine, and all is sweetness and light.
EDIT: If anyone can add peer-reviewed, reasonably-safe, well-studied neuroenhancement lifestyle choices (food, supplements, pharma, etc.) that aren't just spam/gimmicks, that would be interesting.