One of my early working programs: Tetris-3D (download)

• Fully written by me in 2007.
• Developed in assembly language (MASM), its size is 24 kilobytes!
• The main feature is 3D rotation (may seem complex at first glance, but then you quickly get used to it).
• The game uses the OpenGL library (theoretically should work under Linux).
• Implemented a multiplayer mode where players can compete against each other (pressing space sends obstacles to the opponent for earned points).
• To remove balls, you need to connect them in groups of 3 or more horizontally, vertically, or diagonally.