Fluid is a realtime fluid-dynamics model and rendering engine that uses OpenGL to create the effect of flowing liquid on your screen.

The Fluid engine allows complete freedom to design your own unique Fluid Themes that can be saved, reloaded, traded, and even shared via Rendezvous with a Fluid Theme Server (included in the distribution). When you run a Fluid Theme Server every machine on the local network will have access to your saved Fluid Themes.