I don't know if your brain releases a wonderful chemical when you see something that jolts it for a moment or not, but it's definitely a unique feeling, isn't it? It's not quite deja vu, but there's a similar bodily thrill that goes along with it as your brain tries to figure out what's going on.
So there's some appeal to these pics, as well as the challenge to wrap your head around them. They really do throw your brain for a loop.