FlightGear
FlightGear is an open-source flight simulator. It is developed by skilled volunteers from around the world.
FlightGear has the ability to model a wide variety of aircraft. Currently you can fly the 1903 Wright Flyer, strange flapping wing “ornithopters”, a 747 and A320, various military jets, and several light singles. FlightGear has the ability to model those aircraft and just about everything in between.
OpenRCT2 is an open-source re-implementation of RollerCoaster Tycoon 2, a construction and management simulation video game that simulates amusement park management.
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Realistic Racing game with BMW M3 on the Nurburg Ring GP-track. Players take control of a professional edition of BMW. The car can be visually modified.