Beep baseball is the classic American pastime adapted for the blind and visually impaired. In order to appreciate the athleticism of the game, and the fun that most sighted folks are missing, here's a video of beep baseball in action.
The ball used contains a beeping device that is loud enough to aid in sightless location. The six players on the field are helped by a sighted pitcher, who announces "pitch" or "ball" as they toss to a sighted catcher. Batters are allowed four strikes and one pass, but the fourth swing must be a clear, defined miss. The game has six innings, the standard three outs per inning, and two bases, not three. Baseball's traditional tile-like bases are replaced with padded cylinders that stand four feet tall and give off a distinct buzz once activated. The batter doesn't know which base will be activated, but must run to whichever sounds, tackling the base before defense has a chance to field the ball. If the runner makes it in time, a run is scored. Two sighted "spotters" also play the field and call out which direction the ball has headed using a system based on numbers assigned to each outfielder. Spotters can only announce one number, and the outfielders must communicate with each other to locate the ball. Cheering is discouraged because it interferes with play.
Update: A recent article from the Wall Street Journal documented the West Coast Dogs and their quest to win the World Series of beep baseball.
(thx jesse)