In the past, a short sleeve button-down shirt may've conjured images of nerdy guys like Dwight Schrute or schlubby Bible salesmen, but they've been gathering steam with the style set for a while. And this summer, it seems like every designer and mass brand is offering a stylish take on this warm weather staple. Cut from lightweight cottons with a more streamlined fit, they make for a sharp alternative to your everyday polos and T-shirts. They come in a wide range of colors, prices and patterns, but we're partial to the striped varieties, like these featured here. Sport them with everything from your jeans and chinos to shorts on the weekend, and don't be afraid to cuff the sleeves once or twice. But remember, if you're going to be flashing some bicep, make sure there's a little muscle tone there. A few push-ups never hurt anyone.