Pinterest is another social sharing website.
I wrote a post a little while ago about Stumbleupon and how it is essential to set up an account there if you are a blogger.
Pinterest, has lately become another source of great traffic. For one post alone, shared on Pinterest, I got 166 visitors within a few hours!
Pinterest essentially revolves around sharing images. I wrote a post a little while ago about the importance of using images in your posts.
Advice: Sign up with Pinterest, use images in your posts and share these images every time you post.