James Randi is an internationally known magician (as The Amazing Randi), psychic debunker, and winner of a MacArthur Foundation "Genius Grant." He was a founding fellow of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP). He is perhaps best known for offering $1,000,000 (via the James Randi Educational Foundation) to anyone who can successfully demonstrate psychic powers under conditions mutually agreed on by the challenger and himself. Starting with a $10,000 prize over 25 years ago, no claimant to psychic powers has ever won the money.
Randi has pursued "psychic" spoonbenders, exposed the dirty tricks of faith healers, investigated homeopathic water "with a memory," and generally been a thorn in the sides of those who try to pull the wool over the public's eyes in the name of the supernatural.