Super Planet Crash

Super Planet Crash is a simulator inspired by the workings of an orrery, simulating the movements of planetary bodies around a star. Unencumbered by gears and cogs, the simulation is able to get more into the erratic side of cosmic motions yielded by gravitation and other factors of astrophysics. The game's challenge is, in a nutshell, to pack a simplified (flattened 2D) solar system with as many high-gravitation planetary and stellar bodies for as long as possible before one is cataclysmically slingshotted or otherwise ejected (typically following a collision with another planet) from the system's 2 AU (astronomical unit) outside boundary. There are a variety of object weights (a factor of size and density) the player can choose from, ranging from Earth-sized all the way to dwarf stars, with the point value (and increased likelihood of setting off some apocalyptic cascade) increasing as you go along the scale. Bonuses are also offered for "crowdedness" and a planet-hability factor. The maximum number of player-introduced bodies is 10, plus (in the default template) one star and one Earth-sized planet initially present in the system, and the simulation plays out for up to 500 (in-game) years if uninterrupted by planet-crashing.