Break apart and shoot asteroids while avoiding enemy ships (I didn't get around to making them shoot). Design your ship, change the game options, and enjoy the sound effects.
Tetris. Do you like the play on the title (Turing, Tetris)?
Tic-tac-toe. What about this one?
I had to make this classic game. I didn't want to spend a lot of time making it fancy, but at least I made sparks fly whenever a brick is hit. The ball bounces off the paddle as it physically would.
As you level up, you gain more rocket launchers and shoot faster, and you gain more thrusters and move faster. The enemies also move and shoot faster with more damage.
Eat the blue circle while avoiding the growing red circles. Pacman chomps while moving around.