Like Tetris, Sokoban relies on a mind-numblingly simple concept and, in doing so, ensures addictive qualities beyond question.
A little man is trapped in a series of mazes, each one containing a number of wooden crates. On the floor are dots, and the only way to progress through the levels is to push all of the crates over the dots, thereby unlocking the door to the next maze.
That may sound like a none-too-exciting gameplan, but just you wait until you move just one crate into the wrong position and have to reset the screen and begin from scratch! Sokoban is an infuriatingly addictive little title; not quite on a par with Tetris, but not far off.