Great! I know, there is a website, where one looks for such pen friends. Can you call it?

Sure, this is it - http://www.postcrossing.com/ Actually, on this website people send only one postcard to each random person and they don't keep up a correspondence, so to make pen friend will be quite difficult. But lots of users "interested in direct swaps" as they say, interested in exchanging postcards without registration on the website. So it's difficult, but possible :)

А я тут закончила только что подписывать открытку. Уже две подписала XD Блииин, я накатала огромные простыни текста! Как книжка?)