We have Katie Holmes to thank for the ubiquity of the knit bra — ever since she hailed a cab wearing one in NYC last fall, they've popped up everywhere, and honestly, we're thankful. Where would our leisure looks be without one? Whether you're styling one with colour-coordinated sweatpants, are mirroring the actresses' chic cardigan-set ensemble, or toss one on with a t-shirt and PJ pants, it's the elevated comfy bra trend we never knew we needed.