When it comes to yoga tops, I like mine to be a little fitted. Otherwise, mine flips upside down and over my head every time I try a downward dog. Not cool. This cuffed t-shirt from Old Navy, on the other hand, is super cool. It comes in a variety of great colors, too. Old Navy's basic ribbed tanks are also great for working out. They're long enough that you won't be self-conciously pulling the tank down over your hips, and light enough to layer a couple for maximum cuteness.
Danskin Plus Cotton Bootleg Lycra Pant - comfortable and versatile enough that I could meet up with friends for a post-workout cup of coffee (ok fine, glass of wine) without feeling all gym-sey.I like these roll-top waist Yoga Capris from Junonia. They come in black, white, and ice blue too. It'd be really easy to suddenly find yourself wearing these 24/7, though. They should come with a caution label.
Photo credit: Fitsugar.com; Danskin.com; Junonia.com; OldNavy.com