25 Dollars Greg Louganis

Greg Louganis won both the springboard and platform diving gold medals at the 1988 Seoul Olympics — a feat made extraordinary by what happened during preliminaries, when he struck his head on the board during a reverse 2½ pike and required stitches, then returned to complete the competition and win. The Marshall Islands issued a series of commemorative silver dollars tied to that year's Games, this being among them.

Louganis later disclosed he was HIV-positive at the time of the accident, a revelation that generated significant medical and ethical debate when it became public in 1995.