The Frankfurt Motor Show, which alternates venues every year with Paris, marks the beginning of the auto show season, making it an important stage for manufacturers to display their latest and greatest. Supercars, step aside; this year was all about green. Not the color – though there was a bit of that too – but rather plug-in hybrids, regular hybrids and a variety of alternative fuel concepts as well. But the real stars of the show were the unique electric car concepts that illustrated how strong (and varied) the EV market will be. Here are our top 5.