Tetris. Make Tetris.

A leveled platformer game where you experience the average life of a block of cheese

Hmmmmm how abt… a game where you have to play ten (real life) days trying to escape? Like day one you get familiar with your surroundings, day two you have a lunch tray in the room and the wall is weaker than before, and everyday the player has to do everything try thing they can with their items they got that day, because ex: day one you have a basket, and day two you lose the basket byt get like a wrench?

Clouds

Maybe (if you know how to make it) make a game where you can test physics?

Noise generation (like they use in Minecraft)