Evasion belt agility trainers and reaction balls are two fun ways to develop lightning fast reflexes and reaction times.
Evasion belts are fantastic for developing fast reacting footwork and developing a good sense of distance control whilst reading and reacting to your opponents reactions. These are the same mission critical skills needed whenever you square off against any opponent in a physically competitive sport.
Reaction balls bounce in a very random and unpredictable manner so to catch the ball you have to develop the ability to be able react in a very instinctive manner and move in any direction faster than you can possible think about how you should react.
In martial arts combat and with other competitive sports fast reaction times often get down to being able to use the same reactive instincts as with the reaction ball and being able to predict what the opponent is going to do next in order to react fast enough.