There was a time, before GTA, when parents let their children play video games - as long as those games were Windows freebies like Hover! and SkiFree. Or Win95 screensaver "game" 3D Maze, which has reappeared as a Layar add-on.
If you never sat in front of a PC for hours on end watching the magical 3D Maze screensaver spin around in front of your eyes, then I pity you. (Your parents could probably afford a PlayStation, I'm guessing).
AR Labyrinth Game is a free add-on for Layar, but you'll still need to download it from the Market and use it as a skin in the augmented reality app. Holding the phone out in front of you, your surroundings are instantly transported into the 3D Maze settings, and you can even choose the walls, floor and ceiling patterns, too.