I don’t know what’s the worst (or best) part: that HTML 5 is being used for this kind of gimmicks, or the fact that there’s people who are entertained by a gray cat who shits rainbows while flying- er, running across the universe with a pop tart glued to its back. Does that make sense? No. Does it need to make sense? No — this is the Internet, after all.
Feel free to click the links, but don’t blame me if your score in future IQ tests drops by a significant amount as a consequence.
Protip: nyan.cat works best with Google Chrome. Firefox 4 and Opera 11.10 miss the rainbow animation for some reason, on Linux at least. Not that I care, really.