Stanford:
Riedel-Kruse and his lab group have developed the first video games in which a player's actions influence the behavior of living microorganisms in real time – while the game is being played.
These "biotic games" involve a variety of basic biological processes and some simple single-celled organisms (such as paramecia) in combination with biotechnology.
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The player attempts to control the paramecia using a controller that is much like a typical video game controller. In some games, such as PAC-mecium, the player controls the polarity of a mild electrical field applied across the fluid chamber, which influences the direction the paramecia move. In Biotic Pinball, the player injects occasional whiffs of a chemical into the fluid, causing the paramecia to swim one direction or another.