A maneuver used in professional wrestling. The
executor sets it up by placing his opponent in a standing
fireman's carry. He then proceeds to drop the user sideways so that his head crashes into
the canvas. (Although taller wrestlers performing the maneuver often will flip the person over completely.)
The move was popularized in the US in the mid-90s by Louie Spicolli in ECW, although it likely was already being used in Japan.
"It almost looked like the
Brooklyn Brawler had the match won, but
Tommy Dreamer hit him with the Death Valley Driver, knocking him
out cold."