I really like Orbiter. I want to thank Dr. Martin Schweiger for developing it and making it freely available to the world. Thanks to him, there's a truly international "virtual space program" going on right now -- with people in many countries creating add-ons for Orbiter and using it to teach and learn about physics and space flight, to explore the possibilities of space, and even to simulate possible future missions and systems such as space elevators. I think it's a great educational tool, and I've got my own campaign going to help teachers and students make better use of it (I'm currently working on a teacher's guide to supplement the tutorial book I wrote).
But you can also use Orbiter to just fly around the solar system and appreciate how beautiful it is. With the help of an indispensible add-on called Orbiter Sound, Orbiter is also an MP3 player for your PC! So you can listen to music while peacefully orbiting the Earth or any other body in the Solar System. Very relaxing. The screen shot shows Jupiter rising over the sulfurous surface of Io, Jupiter's highly volcanic moon. A futuristic "Delta Glider" space plane is firing its main engines to leave orbit.