If you’re already growing your marketing presence and getting exposure on Facebook and Twitter, perhaps it's time to grow bigger by thinking... smaller. There are tons of new networks with targeted audiences gaining popularity and generating buzz, and many brands are finding success with the targeted audiences of niche social media sites. We’re not saying you should abandon the bigger sites like Facebook – they’re great for getting exposure to a bigger audience. But when you need to hone your message just right, niche networks such as Pinterest, Instagram and Turntable.fm are the place to do it.