Where does the US flag fly 24 hours a day, 7 days a week and 365 days a year?

The Moon

Photos here:
http://sservi.nasa.gov/articles/apollo-moon-flags-still-standing/

* Fort McHenry National Monument and Historic Shrine
Baltimore, Maryland (Presidential Proclamation No.2795, July 2, 1948)
* Flag House Square (Mary Pickersgill's "Star Spangled" House)
Baltimore Maryland (Public Law 83-319, approved March 26, 1954)
* United States Marine Corp Memorial (Iwo Jima)
Arlington, Virginia (Presidential Proclamation No.3418, June 12, 1961)
* On the Green of the Town of Lexington
Massachusetts (Public Law 89-335, approved November 8, 1965)
* The White House
Washington, DC. (Presidential Proclamation No.4000, September 4. 1970)
* Washington Monument
Washington, DC. (Presidential Proclamation No.4064, July 6,1971, effective July 4, 1971)
* United States Customs Ports of Entry
which are continually open (Presidential Proclamation No.4131, May 5, 1972)
* Grounds of the National Memorial Arch in Valley Forge State Park
Valley Forge, Pennsylvania (Public Law 94-53, approved July 4, 1975)

http://www.crwflags.com/fotw/Flags/us_24hr.html

[Added reference link - McG]

If a flag is not lighted at night, it is in violation of the US Flag Regulations.

http://www.flagandbannersupply.com/flag-etiquette.htm

http://www.ushistory.org/betsy/flagetiq.html

But do those regulations apply on the Moon, which is not US territory?

Well.....IF we placed a Flag there then technically the direct area HAS been claimed as US soil. That is the purpose of a Flag.

The Soviets/Russians claimed previously unreachable areas of Antarctica by dropping darted Flags out of low flying planes!
We Americans did it first with Admiral Byrd.

http://www.south-pole.com/p0000107.htm