I'm of the belief that eyebrows are the most important feature of your face. Even when I go completely make-up free, I make sure that my brows are filled in and shaped. For years I was using brow powders, but never totally satisfied. It was hard to get the shade right, they were annoying to apply, and I always felt like I had two eyebrow-shaped shadows floating above my eyes.
A few weeks ago I was in Sephora and stumbled upon Anastasia's Brow Wiz pencil ($20, sephora.com). It was the skinniest brow pencil I had ever seen and it piqued my interest. I tested it out and immediately fell for it. Since the tip of the pencil is so thin, it allows you to draw featherlight strokes that resemble hairs, filling out your eyebrows in any over-plucked or sparse areas. With this pencil, I could completely reshape my barren looking brows. I was in love.
If you're stumped on what to use on your brows, this is the product for you. It comes in three shades and has a "spooley" brush at the other end so you can soften the lines and tame your brows too. It's magical, really.