Pacer Women’s Running Skirt by Nike
Are loose-fitting shorts annoying to run in, but you're not quite ready to go the full-on spandex route? Try a running skirt instead, which modestly hides a pair of tight shorts underneath. This style from Nike is made of moisture-wicking Dri-Fit fabric and comes with a handy pocket for an mp3 player.
To buy: $45, zappos.com.