Another game from the 14th Ludum Dare competition, Mindwall is a simple, original puzzle game with, given its short development time, remarkable polish.
At the level beginning, you see a 3D wall with some holes in it. It moves toward you quickly. Somewhere on it is a red square that you move with the arrow keys. At lower left is a wireframe showing "your shape" -- at the first level, a rectangle composed of two squares adjoining horizontally. Your objective is to move the red square on the advancing wall, then press CTRL to punch a one-square-sized hole in the wall. This, along with adjoining, pre-existing holes, must create a space large enough for "your shape" to move through. If the wall fills the screen before you make a selection, you lose. And if your selection is incorrect, you lose. As levels advance, "your shape" changes.
A very simple structure, with an element of time pressure and the need to perform spatial reasoning quickly. The graphics are minimalist, but minimalist in an attractive way, and the soundscape of the game gets across a bit of a sense of onrushing doom. The animation when you lose (a screenshot of which is shown above) is attractive as well.
When the only real criticism you can come up with is "it's too short," you know the game is really quite good.