Lately, I don't even consider wearing a shirt unless it's a turtleneck. Not only are they super slimming; they're also (no surprise) super warm. A turtleneck is more than a sweater — it's a great way to look a little more polished when you just want to feel cozy. Still, even the best turtleneck can seem a bit limiting, style-wise. With that in mind, I took to my closet lab, where I came to the firm conclusion that the ever-tricky turtleneck is back and more useful than ever. It can be worn with a suit or even under a dress to a fancy occasion. Sorry, other shirts — I'm picking a favorite.