vectorSpace is a game project of mine, obviously inspired by classic vector-graphics spaceship games like Spacewar! and Asteroids. Currently, it's in more or less a pre-alpha status; I have a simple but reasonably nice vector-graphics simulation written for SDL, but I'm still working on building the object physics engine. Eventually, vectorSpace will be a 2D space exploration and combat game somewhat like Epic Megagames's Solar Winds.
vectorSpace is written in C++ and uses SDL for input and video. There is very little game content at present, but you can pilot a spaceship around a screen with a star and some asteroids, all of which exert gravitational pull on each other. You can download the source here, or a Win32 executable here.
9/23/09: Update! In a fit of coding, several things have been added or improved: