Galactic Arms Race is a hybrid space shooter and Action RPG with single player, co-op, and PVP on dedicated servers for up to 32 players. Players fly a space ship, destroy enemies, earn money and experience, gain levels, find items, and upgrade their ships. The main feature that differentiates GAR from other space shooters is a procedural content generation (PCG) system that produces unique particle system weapons. The game attempts to create weapons that players will like based on usage statistics of existing weapons using a custom version of the NEAT evolutionary algorithm. GAR is one of the earliest video games to incorporate procedural content generation that is automatically and implicitly driven by player choice.
Source: Wikipedia, "Galactic Arms Race", available under the CC-BY-SA License.