Not sure if this has been mentioned before & if it has, sorry for not checking.
Just over a month ago I came across the Postcrossing site, http://www.postcrossing.com, & am happily swapping postcards with others throughout the world. What is good is that it's free, albeit that it accepts donations.
On their home page they have this phrase which sums it up:
“send a postcard and receive a postcard back from a random person somewhere in the world!”
One thing that is funnily is that you would expect that those involved come from countries that are largely populated. The States have more postcrossers than any other country & no surprise however take a guess at the next country that has more registered users.......it's Finland!
As for ther UK, sadly 3% of registered users.Have a bash.