[6ren]

We have to mention the famous mathematician Paul Erdős http://en.wikipedia.org/wiki/Paul_Erd%C5%91s

  After 1971 he also took amphetamines, despite the concern of his friends, one of
  whom bet him $500 that he could not stop taking the drug for a month. Erdős won the
  bet, but complained that during his abstinence mathematics had been set back by a
  month: "Before, when I looked at a piece of blank paper my mind was filled with
  ideas. Now all I see is a blank piece of paper." After he won the bet, he promptly
  resumed his amphetamine use.

He also liked coffee.

Note: effective programming in the real world is absolutely not the same as mathematics - but some would argue that the essence of it is.