Fishie fishie fishie...on my screensaver!
This is hands-down the coolest screensaver program EVER. Seriously, it's so cool I can't stand it! It turns your computer into a goldfish aquarium. The fish are adorable and they move very realistically, although their tails wiggle just a bit too much compared to RL fish. You can have several different tanks with up to 5 fishies in each, or a pond with 10! The free version lets you see the fishies, but if you want to use it as a real screensaver and customize it then it's 20 bucks. Well worth it, at least to me. But then I'm a wee bit obsessed with goldfish, in case you hadn't noticed. ;D