This game tests how quick and accurate your mouse skills are. Buttons randomly appear on-screen with a number on them. You have to click the buttons that many number of times. Sounds simple, but it can be addicting. Highscores are implemented in this game.
It can also be used as an FPS trainer. It has all the same challenges as a regular FPS game: target acquisition, quick and accurate mouse movements, and seeing how many times to fire the gun (to click).
Libraries/Engines used: Slick2D