What do cats, babies and that old guy in Starbucks have in common? They understand the importance of a good nap. A new study found that even when subjects slept just two hours per night, two 30-minute naps could restore healthy levels of the compounds that regulate stress and immune function. "Tell us something we didn't know," say famous nappers Napoleon Bonaparte, Leonardo DaVinci and JFK—rumor has it they never bothered going to bed, fueling their genius with short bursts of temporary slumber. Do you rely on naps to get you through the day, or do they make you more tired than you were in the first place? Let us know in the comments.