Internet Email Country Codes

Have you ever wondered where your e-mails are coming from. One thing I miss about e-mails compared to traditional letter-writing is the absence of an address. Whenever I can, I try to remember to sign off as "Robert Murray, Edinburgh" (or Robert Murray, Goldenacre", or "Robert Murray, Edinburgh, Scotland", depending how far away the message is going.
However, when an e-mail comes in, and you have no idea where the writer is, look at the last two letters of their e-mail address - very often it will give you the answer, and make everything so much more interesting !

A thought - has anybody yet started trying to collect a complete set of all the different countries ?   What would such a collector be called ?   An "Ecodologist", a "Cyber Suffix Collector", a "clickelist", a "Supernerd"  ?