Don't let the name fool you. A diaper bag is much more than a simple over-the-shoulder sack that houses absorbent, disposable underwear for your little ones. It's actually an indispensable carryall that can rescue you from the unexpected. Whether you're a mom, dad, grandparent, or nanny, a sturdy diaper bag filled with all the essentials is a must. "Beyond the practical," said Ingrid Kellaghan, founder of Chicago's Cambridge Nanny Group, "investing in a good diaper bag will save you lots of time and energy by keeping you organized when you're on the go."