According to the U.S.-funded World Values Survey, Denmark is currently the happiest country on earth (Zimbabwe is the least happy country). Puerto Rico and Colombia also rank highly, along with Northern Ireland, Iceland, Switzerland, Ireland, the Netherlands, Canada and Sweden.
Of the countries in this list, Nelso listings currently cover only Denmark, although we do plan to cover Holland and Switzerland soon.
I've always been interested in providing listings for Iceland on Nelso (particularly Reykjavík), but unfortunately, neither Yahoo nor Google have street-level maps for Reykjavík. I have no idea why a country like Iceland would not be represented on Google maps; perhaps there are some legal issues to be sorted out?