Sextris

Sextris is one of the infinite versions based on the original Tetris (or more concretely, a softer version of the contemporary Porntris). As it's name suggests, this game is directed at a mature audience. This is because this version contains several erotic images with celebrities on them. These images will -initially- appear in a covered way as the background of each level, but will slowly be uncovered as you complete lines.