: Mixed Reality Auto Racing is game for two to four players. The track is built from tangible objects (e. g. little cardboard houses) by the players and can be changed and rebuilt during the game. The game has been developed as a public Mixed Reality installation which can run by itself; it is controlled by the players without instruction. The focus of development was experimenting with input and output possibilities of the increasingly invisible computer in a gaming context; in this case using an established and robust method (video tracking) and everyday hardware (joysticks, projector, web cam). The mixture of the real and virtual space through the tight interconnection of tangible and projected objects in one place emerges as an interesting concept. 1 Description MR Auto Racing (Figure 1) is game for two to four players who come together face-toface in one place (e. g. around a table). The racing track is built by the players from tangible objects (e. g. little cardboard houses) (Fi...