Crossfire is a multi-player graphical arcade and adventure game made for X. It has certain flavours from other games, especially Gauntlet and the rogue-like games (Nethack, Moria, Angband, and Ragnarok). Any number of players can move around in their own window, finding and using items and battling monsters. They can choose to cooperate or compete in the same world.
Blender is a free 3D animation studio. It includes tools for modeling, sculpting, texturing (painting, node-based shader materials, or UV mapped), UV mapping, rigging and constraints, weight painting, particle systems, simulation (fluids, physics, and soft body dynamics and an external crowd simulator), rendering, node-based compositing, and non linear video editing, as well as an integrated game engine for real-time interactive 3D, and game creation and playback with cross-platform compatibility.
ICBM3D (Inter-Continental Ballistic Missiles, 3D) is a 3D game of defense. Like the original "Missile Command" and its clones, this game places you in control of Anti-ICBM weapons which you use to destroy an onslaught of missiles (and other nasties) which are dropping onto your nation. The game ends when your cities have all been destroyed. You only gain replacement cities by acheiving certain score thresholds during each attack. The differences between Missile Command and ICBM3D is that ICBM3D, as the name suggests, provides a 3D perspective. You take advantage of X-Window's 3-button mouse to control your firing sight in 3-dimensions and change your viewpoint.
Mondriaan produces a set of images that look a lot like the paintings of the artist Piet Mondriaan. By way of selection and genetic operators this set can be manipulated by you. You can try to find images that you think look even more like Mondriaan art, or search for images you find attractive.