Daylight Savings Time
Widespread confusion was created during the 1950s and 1960s when each U. S. locality could start and end daylight saving time as it desired. One year, 23 different pairs of DST start and end dates were used in Iowa alone. For exactly five weeks each year, Boston, New York, and Philadelphia were not on the same time as Washington D.C., Cleveland, or Baltimore—but Chicago was. And on one Ohio to West Virginia bus route, passengers had to change their watches seven times in 35 miles!Much more here (via Gruntdoc)
Personally, I enjoy having the extra daylight in the evening especially now that I own a house with a patio and nice view, even though I find getting up the first few days very challenging and I have less daylight for am runs.