The Cacheability Engine will check a URL you feed it for several things that will affect a Web cache, including web server clock skew, expires and Cache-Control headers, Last-Modified date presence, validation of LM date, Content-Length presence and more. It makes it easy to see how a cache will treat your content. There are also public engines running, so you don't have to install the software to use it for Internet-available sites.
Cadaver is a simulated world of cyborgs and nature in realtime. The battlefield consists of forests, grain, water, grass, carcass (of course) and lots of other things. The game server manages the game and the rules. You start a server and connect some clients. The clients communicate with the server using a very primitive protocol. They can order cyborgs to harvest grain, attack enemies or cut forest. The game is not intended to be played by humans! Instead the idea is that you write artificial intelligence clients to beat the other artificial intelligences.
CAFire is a small toy that displays a burning trace after the mouse pointer in X. It can work in a normal window or in the root window. A simple background preservation mode enables you to have your favourite background image while running CAFire in the root window. Different effects can be obtained by setting various parameters of the underlying cellular automata, and sample parameter files and colormaps are included.