Free drinking water. You can drink the tap water.
High speed internet.
International cuisine. I will write more about this later, but in the DC area, one can get good Vietnamese, Ethiopian, Korean, Chinese, Indian, Pakistani, Salvadoran, Japanese… you get the idea.
International people. Many embassies are located here.
Public transportation. Between the train, bus, and light rail, you can get many places for 3-10 dollars.
Availability of things – Amazon is sometimes delivered the next day or faster, and some shops are open 24-7.
Free museums, free concerts, free meetings, and free libraries. The Smithsonian is a collection of 21 museums and almost all (I think only the one in New York charges an entrance fee) are free to enter.
National Airport (DCA). Having an airport on a metro line and within a mile of DC is gold. Dulles is also on the metro but 25 miles away.
People like dogs. Oh, wait, that’s not just here. But I still think it’s a good thing about being here.