Hawaii and Arizona burn daylight like there's no tomorrow
Hawaii doesn't adhere to DST, maintaining an easy-to-remember time zone of GMT -10:00 year-round. Strangely, in the Winter, Alaska is on the same time as Hawaii -- so, while their climates are world's apart, for half the year, both states observe HAST (Hawaii-Aleutian Standard Time).
Try saying Hawaii-Aleutian three times fast.
Arizona (GMT -07:00) has also ignored DST since 1975, owing to the state's monumental heat; as ABC15 points out, if Arizona did observe DST, the sun would rise at 6:30 am instead of 5:30 am, and set at 9 pm instead of 8 pm, making for a much less productive workforce, according to a study conducted by Michigan State University.
A number of U.S. Territories -- such as the Virgin Islands, Puerto Rico, Guam, and American Samoa -- also don't observe DST. But they're not stars on a flag, so no one really cares.