The WWW is huge. And It’s expanding to infinity. Just like our universe there are as many websites as stars and planets in space.
I wonder if any of us explored some sites that are truly unique or informative. Or just plainly fun. Clean fun.

Let me start: http://www.popurls.com
You see the weirdest, most unbelievable stories or pictures getting popular. Just watch Digg.com

http://www.galaxyzoo.org/Tutorial.aspx
Feel like indexing galaxies ? This is a place for you.

Of course there is a lot more. It is your place to suggest, but please full websites not just pages.