During my final year at university, I undertook a major project developing a cross-platform, multiplayer, 3D video game engine. The project took a typical agile development approach to develop a reusable game engine over a series of iterations. Each major development iteration also delivered a small multiplayer game alongside the engine.
The final project report can be downloaded here (the .pdf may take a while to load).
Hearts (first game development iteration)
Asteroids (second game development iteration)