Space Engine
SpaceEngine is a realistic virtual Universe you can explore on your computer. You can travel from star to star, from galaxy to galaxy, landing on any planet, moon, or asteroid with the ability to explore its alien landscape.
You can alter the speed of time and observe any celestial phenomena you please. All transitions are completely seamless, and this virtual universe has a size of billions of light-years across and contains trillions upon trillions of planetary systems. The procedural generation is based on real scientific knowledge, so SpaceEngine depicts the universe the way it is thought to be by modern science. Real celestial objects are also present if you want to visit them, including the planets and moons of our Solar system, thousands of nearby stars with newly discovered exoplanets, and thousands of galaxies that are currently known.
Racing video game by EA based on illegal street racing, tuning and police chases. It has RPG style levelling up and improved cars to unlock.
Classic racing game GTA2. Grand Theft Auto 2 retained the overhead viewpoint of Grand Theft Auto, as well as the car-stealing/telephone-answering formula of the original.
Duty Calls is a very short and easy to play Call of Duty parody, that makes fun of modern warfare games.
Classic real time strategy game
FlightGear is an open-source flight simulator. It is developed by skilled volunteers from around the world.
Celestia is a space simulation that lets you explore our universe in three dimensions. It provides photo-realistic, real-time, three-dimensional viewing of the solar system, the galaxy and the universe.
DOSBox is an emulator that recreates a MS-DOS compatible environment (complete with Sound, Input, Graphics and even basic networking).