Daylight Saving Time ends today—but should we scrap it once and for all? It's doubtful that DST actually helps us conserve energy, which was the original logic. Here are a raft of studies on the subject: Most find that while households do use less lighting during DST, thanks to the longer, brighter afternoons, they also end up cranking up the A/C more, which makes it either a wash or a net loser for energy use. (Hey, if that's the case, maybe we should just permanently set our clocks back two or three hours and live in darkness so that we can really start conserving...) On the, er, bright side, it's possible that DST reduces traffic fatalities and even violent crime, so perhaps it's not a total waste.

--Bradford Plumer