US yellow plates

area codes give you a rough estimate about where you are in canada.
Explanations in french here : http://super-duper.fr/country/canada.php.

Canada : area codes / phone numbers

each swedish county has a different sign for buses.

sweden bus signs

phone numbers are a good way to know where you are in greece. You can play this map no move and try to estimate your position on the map.
Explanations about greek area codes in french here : http://super-duper.fr/country/greece.php