Taped Baseball Bat
One of the biggest problems in professional baseball is the number of broken bats which very often send bat pieces with sharp edges towards players, coaches and people in the stands. My simple solution is to wrap the bat with strong tape with a couple inch gap. The tape won't effect how hard the ball is hit, but if the bat breaks the pieces will be held together.
Reward: I am an unemployed draftsman and if the idea caught on I would like a job lead or 2.