The cardigan is the only entry on this list to be both sophisticated and cozy. Over a dress, under a suit jacket, buttoned, unbuttoned -- the multipurpose cardigan is both an outfit-changing accessory and a shirt for chilly days. In a pinch, a cardigan is also a great casual Friday replacement for the suit jacket. Go green or red to provide your outfit with an instant splash of color. While saggy cardigans have pretty much cornered the market on weekend comfort, a tight, fitted cardigan helps you project a confident workplace demeanor.