France
Surprise: Along with the terrific food and urbane culture, France offers perhaps the friendliest of policies toward American retirees of any European Union nation. Considered most affordable quality health care in the world, plus low taxes for American ex-pats. Paris for wealthy, but Brittany, Normandy and the Dordogne, a short train ride away, are more affordable. Also look at Marseille, Aix-en-Provence and Lyon.
Downside: bureaucracy. Getting Internet connection can take weeks.