Let's face it, it is getting harder and harder for big oil to move the needle on its production numbers and its proven reserves. Each discovery must be bigger than the last. That's why little oil offers such compelling reasons for investment right now. These smaller players are thriving on the U.S. energy boom, and most investors don't even know their names! In this video, Fool.com contributor Aimee Duffy spotlights three small oil and gas producers who are making the most of the shale revolution.