Does anyone know a fun website?

Due to the nature of my job, I find myself on sites like this (which is my new favorite) all day long. Does anyone know of any time-consuming sites that are free, fun and keep you entertained? Other than Facebook/Myspace/Xanga.

Some examples would be:
Of course Fluther! www.fluther.com
PostSecret www.postsecret.com
WeSeed www.weseed.com

Please don’t suggest Yahooanswers, they got old a long time ago! Thanks