I love the new feature on Pinterest. It lets you know if you have already pinned a picture.
It's very helpful for me because I have over 900 pictures pinned to my crochet board. I use to open two windows, one of the main page and one of my crochet board. When I saw a picture that I thought I had already pinned, I would check my board to see if it was there. It was time consuming but worth it to me because I really dislike when I have something pinned twice.
Yay for Pinterest...