Sensi Soft: I think it is some kind of technology company but I have no real clue. I just ended up there. The music is so comforting and if you stay on the main page a minute you can see things moving in the background... like those horses. Then click the arrow to the right and see the next location. It really is a brilliant site and for some reason reminds me of Dr. Who even though I've never seen a whole episode.
Level 2D: This one is a little less exciting but gorgeous nonetheless. I love the old gas station feel and how clicking on different things changes the site (though not as extensively as Sensi Soft). I believe this is a Web Design site and from the look of them they are pretty good. Still I'm not in the market just having fun on the net.
Honorable mention for fun to look at site goes to Ben The Bodyguard. This link is not the homepage but a really neat page within the site. Scroll down and see the action.