Why do you e-mail articles to friends? Or "like" a link on Facebook? Or retweet a post on Twitter?Content that triggers an emotional response is more likely to be shared, according to a recent social media marketing training University of Pennsylvania study of the most e-mailed New York Times articles. What's more, "surprising" stories (like one about free-range chickens hanging out on the streets of New York) were also more likely to be passed along.But the most-shared articles are those that go beyond surprise to actual awe--or what the researchers defined as an "emotion of self-transcendence, a feeling of admiration and elevation in the face of something greater than self." In other words, people share the stuff that ignites a little spark in them.So what does that mean for you and your business? Why should you care about a kindergarten concept like sharing?Because a clear way to generate and nurture leads is to create content: a blog and maybe an e-book and a Twitter stream and so on. But it's pointless (and lonely!) to write a blog that gets no visitors and zero comments and, consequently, affords no traction for your lead-gen efforts.Websites that facilitate sharing generate seven times more mentions online than those that don't (see below). So how do you grease the sharing skids? How do you get folks to share your stuff online? Here are some ideas.Websites that display Twitter sharing buttons are linked to on Twitter nearly seven times more often than sites that do not display tweet buttons. Among the 10,000 largest websites, those that feature Twitter share buttons are, on average, mentioned in 27 tweets that contain a link back to the site, whereas those not featuring tweet buttons are mentioned, on average, social media marketing classes in only four tweets that contain a link back to the site.Create at least some winged content that can soar across the social web. Create things people want to share and that they'll find useful, helpful or just plain fun: branded e-books, white papers, audio or video downloads, infographics, PowerPoint slide decks, research charts, tools or photos.