Paranoia: Troubleshooters is a set of free rules for a card game based on the West End Games’ Paranoia RPG.
Board Games
Mechbrawl Card Game
Mechbrawl is a free expandable card game. In it, you face off against your opponent in a giant, customizable war robot.
Catan Horror
Catan Horror is a set of mashup rules for combining the board games Arkham Horror with Settlers of Catan.
Time Tripper SPI Game Java Implementation
Here’s a Java implementation of the old school game from SPI: Time Tripper.
Hidden Empires — Ant Colony Game
Hidden Empires has got a pretty unique theme:
Hidden Empires II is a game for 2 to 6 players where each player assumes the role of an ant colony. You will guide your colony as it attempts to grow and thrive in a hostile environment while competing for resources with neighboring colonies. Your colony will employ unique survival strategies based on those of real world ant species. To win the game, you must give your species the best chance of survival by producing more reproductive ants than your opponents.