There is no answer to this, as it depends on the character, skills, experience, expectations and investment aims of the individual.

For me:
Syria - because my wife is from there, and though until recently it was not possible to mortgage property, my wife has made very decent returns on fully invested cash in property. She's over there right now buying our 5,500 sq ft retirement home for about £200K (and 50% mortgages are now available, albeit at 9% interest)

Spain - for the simple reason that we saw an attractive, scalable opportunity, and registered an S.L. to get after it.

UK, UK and UK
I'm buying as much as they'll let me buy here in 2008. I think the last opportunity we had like this was in the period 1993 to 1997. This time around, we've got far more funds to play with. Just watch the yields climb in UK property in the next five years.

There's also a soft side to making this decision. If you are going to invest overseas, at least make sure you enjoy visiting that place. If things go t*ts up, you will have to go there time and again to sort things out, and it may as well be somewhere you enjoy going to.