listed from most expensive to cheapest... use at your own risk.... YMMV
http://www.provigil.com/
if I recall correctly, my max was nearly 40 hours, no sleep, almost fully alert/aware the whole time and got so much done. lots of doctors, drivers, etc take it... kinda replaces the need for sleep. I don't recommend driving, working out or sex while on a long provigil stretch.
another one is "Focus Factor", while lots of people online say its BS, one of my friends loves it.
Metabolife, one of my friends takes it so she can curb her appetite, but she says it makes her very "alert" and she can work & paint better when she's on the stuff.
and possibly, for memory: Ginkgo (YMMV)
http://en.wikipedia.org/wiki/Ginkgophyta
doesn't work for some.
or you could try working out every morning (30-60+) and maybe again in the evening (30+)... improves my focus greatly.
good luck.
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