Some of the Middle Eastern countries (Saudi in particular) accept FAA quals. Also some African and South American countries might.
From what I've found, if the country is "aligned" with a European country, i.e. The Bahamas is ex-UK colony, their Commercial requirements are broadly based on CAA or JAA licences.
There were rumours that Sabena liked to hire FAA qualified pilots. I don't know how true that is though. There maybe some Euro operators who run N regs too.