Germany for a fair chunk of my childhood (army brat) and in adulthood my job has helped me get around and keep that wanderlust going. I became accustomed to upping sticks every 2 or 3 years with my dad's postings.
Taiwan for 9 months or so in 2002/3
Dubai for a year in 2006/7
Other places I've had short stints in include USA (Minneapolis) for 4 months. Could have been longer, but the wife wasn't keen. Also Cambodia, Holland, Libya (friendliest people ever), Qatar, Bulgaria, Cyprus.
Favourite places have been Berlin (was only 10 but have good memories and have been back twice), Taiwan and Cambodia. Not all been good, though. Missed my family when I was away, especially my 2 kids, and I fell too easily into the expat drinking culture sometimes. Good times were had but I've paid a price with my health.
I don't know if I'd move abroad again. As bad as this country is becoming, I'm settled more now and I'm hopeful it will turn around again soon (if people wake up). It does have a lot to offer in terms of culture and scenery and decent people (mostly). If I was to move, it would maybe be to Scotland or Europe.