Pinterest was one of the hottest new social media sites of 2011. From wedding planning to birthday parties to fashion to interior design, the virtual pinboard site offers users the chance to create different boards of webpages and photographs they like or want to save for later. Food and recipes are one of the sites most-pinned topics. In addition to allowing you to save ideas for an upcoming holiday or dinner party, many prominent brands and bloggers have started using the site to show off the things they love. Be careful though, you can easily lose an entire afternoon scanning the boards of your favorite online personalities.