Tesseract: a fourth dimension game is a puzzle game where you need to lead a sphere through a constantly shifting hypercube. It sounds bizarre, and the video does little to really explain it to me (but mind you, I constantly failed physcis in high school). Perhaps you will fare better.
I always assumed the fourth dimension was time. I guess it's shapes shifting dimensions (or whatever is going on here). To be honest, this looks like it will only appeal to a very specific type of puzzle fan, but to those players, I say that the game is available now for $1.99.