We have found caches in four countries so far - France, Germany, Hungary and the UK (our home country). Although we are honour bound to say the UK is a great country to find caches in (in terms of sheer quantity and quality), we really enjoy the caches in France, and we have even been to an event as well. We are off to Israel this year, so hoping to at least find some different ones there too.
We did find a favourite cache container in Hungary, made from the top of a PET tube, a magnet and two part epoxy glue, and we have been making them and using them in some of our caches in the UK ever since!