Just stick a big "Here's what you could build!" link on the homepage that links to your showcase page (assuming that you use your own product). Your story should be the best selling tool you have given the fact you're selling a tool that showcases stories about people.

Plus, why not build some showcases for people who would inspire others to sign up - Mark Zuckerberg, Jennifer Lawrence, Justin Beiber, Elon Musk, Abraham Lincoln, pg, etc (legal issues not withstanding).