Everybody's talked about it, everybody's heard about it, blah blah blah... but I really enjoy Ravelry! I got on it last week, and while I've been utter crap at getting my finished objects and yarn and other things up there for viewing, I'm enjoying the browsing! People make wonderful things! And it's all in one place! Definitely lots of fun. It hasn't gone totally public yet, but it will once they get onto the new servers.
Just in case you haven't heard about it, it's a knit and crochet community. It's also an organizational site for all your fibery stuff. There is a chart to inventory your needles, a place to keep track of all your yarn, a place to post pictures of all your finished objects and a place to queue up the projects you have yet to start. You can also look at everyone else's projects and yarns, and find out about all the substitutions and changes others have made to whatever project you're considering. Sometimes I think I could use a site like that for my life. But then I'd probably spend so much time getting everything entered into it, my life would probably stop, and then it would be useless.
I'm actually spending very little time on Ravelry, but I like that I can look up a pattern I'm considering and see all sorts of finished versions. I also like that I can enter a yarn and see what others have made using that same yarn. Excellent tool, all the way around.