Designing puzzle games must be quite an interesting job. Finding that compromise between intuitive play and challenging sequences can only be described as a tough. Adding to that the idea of forcing people to think in three dimensions and a great idea is buried in the mechanics of exposition instead of extracting fun. Cube, unfortunately, suffers under this problem.
The premise is that the player controls a cube, a six sided square solid, and must proceed to the exit, the highlighted side on a certain surface, in as little time as possible. Gameplay consists of moving along one of the sides of a greater shape. As long as that greater shape has a side to move to the cube can rotate onto it and thus change the orientation of the puzzle. Obstacles such as spikes, which explode the cube and thus end that session, and one-way sections fail to extend the play but instead add greater frustration.
Along with standard play, in several different sections of difficulty, Cube comes along with a level editor. While far from intuitive, it nonetheless allows the player to create their own puzzles with the possibility of sharing them with others.