cppmudd is a small, fast and portable mud driver written entirely in C++ using either standard or widely available libraries (such as the STL). It provides, among other features, support for runtime modifications to the game, ensuring minimal downtime.
Project CodeRacers is a game geared for creative java programmers. It's main idea is that each player will create an own AI agent (the so-called "driver"). The user's driver then will compete against other players' drivers in a simulated car race.