Got a ponytail or bun? Peekaboos hats are designed to keep your head warm and let your hair hang out.

What started as a knitting mishap became a business idea for college student Danica Lause. Knit one, purl two. . . oops—she dropped a few stitches and ended up with a hole. Instead of throwing the hat away, she found a way to put it to good use. To her delight, she received lots of compliments and a new product was born.

Today, there are no mistakes, just machine washable, hypoallergenic hats with patent pending, hidden openings for both high and low ponytails and buns. Once you wear one, you'll be hooked.