From the adorable to the sublime
And if those kittens should be too cute, Papa's gonna buy you Ahem. Let me try that again:
Rowan pointed to Complexification. I will have more to say about this when I get around to posting an entry about utterly gorgeous screensavers (like Electric Sheep), but for now, just go to that Complexification gallery page and look at some of the astonishingly lovely computer-generated art there. Or maybe it's just that I'm sleepy and easily impressed. (I don't find everything on that page appealing, but I really really like some of it.) Anyway, if you click an image, you get a page that lets you see a bunch of samples and lets you try out an applet that implements the algorithm, and you can even take a look at the source code if you want. I predict that I will want to spend many hours on this site as soon as I have some free time, which at the current rate will probably be sometime in 2020.
And with that, off I go to sleep.