In terms of sheer aesthetics, this site from Russia takes a lot of beating. It's difficult to navigate at first, but easy once you get the hang of it. You always find new stuff that you didn't realise was there the first time.
I wanted this guy to do the new label site, but he's not taking on any freelance work (damn!). He just does this for fun.
My English teacher told me about hell.com as sort of a challenge, she wanted to see if I could "get in". Took me a couple days, but sure enough, I sent her a link to the "inside" of hell.com. Very very whacked concept, that site... as a multimedia guy myself, I never really got the point of the "utter confusion interface" from a technical nor artistic standpoint.