I've known Rick since 2001 and was around when he & Todd kicked this off. We've both since moved and it's been a pleasure watching this take off (inter)nationally. In parens b/c I can only verify the "national" part, personally. :) I look for them whenever I visit new places
I've seen several book boxes in Brisbane, Australia, but neither one that I know the location of has been registered as a little free library.
We got at least one of these in my home town in central Italy, which is less than 50k people.
I don't think it works particularly well, but then neither does the actual public library, tho I basically grew up in it.