Tired of those cliched old fish swimming across your monitor? Then check out the Space Wars 3D Screen Saver for Mac OS X (there's one for Windows as well). The demo screensaver features a battle between squadrons of small fighters, but like the aforementioned virtual fish tank, those who register the screensaver can download additional ships. The overall effect is reminicent of a cross between the old Wing Commander games and Babylon 5, with lots of quick turns and explosions.

The render isn't quite as good as the screen shots -- the camera focus is always targeted on the middle of a given ship, and rotates around that axis. It'd be better if you could choose the camera angle so that you could ride shotgun off of one of the fighter's wings and see more of the battle. Expanding the view shows more of the fight, but it can be awkward because again, the actions always focused on one ship. The ships also tend to look a bit too ... pretty. A little battle damage, a little wear and tear, would help them fit in with the background. Overall though, it's a pretty cool little screen saver, particularly if you're tired of the standard options.