I tried putting it off for ages, especially since they require the use of facebook to sign up, but I am so hooked. I'm crazy about sorting things by color, as anyone who has seen my apartment and shelves of books can attest to.. (though the love extends to my closet, my scarves, my bangles, I'm a bit obsessed).
Joining is easy (just let me know if you want in!) and you have a nifty little plug-in that allows you to click on any picture or image you want to save and pin it to a virtual board (here's a link to mine). My pinboards are mostly colors, but you could make boards for your favorite street style looks, bathroom renovation inspiration, great-looking food, you name it. Now if only I could find some of those crystals in pendant form, I'd be a happy woman.