I tried to use 511 out of where I was staying in Fredericksburg, VA, but all I received was an error message. FWIW, this was on an assumption as I didn't see any signs posted that there actually was 511 in this area, though it is a bedroom community for Washington, DC.

As an aside, has anyone ever gotten useful information from those AM 1610 traffic advisories...before being in the situation that caused the sign to light up?