The year's longest day just passed, and that means we are rapidly approaching the halfway mark of 2015. While the S&P 500 has returned roughly 3% this year, that hardly tells the story of the stocks I'm highlighting today. It should be no surprise, for instance, that Peabody Energy (NYSE:BTU) and Natural Resource Partners LP (NYSE:NRP) -- which both rely heavily on the price and utility of coal -- have lost enormous sums for their investors. On the other hand, a handful of tiny and lessor known companies have had booming results.

Does this mean you should sell the winners and buy the losers? Not necessarily. Check out the slideshow below to see the story of the year's top and bottom five movers so far.