User's Country graphic information

Hi all!

I’m developing a site where users as logging-in provide in their personal information the country where they are from. The idea is that later it could be possible to have access to some kind of map or table where it will be displayed to each user the details of where are other users from, amount of users per country, etc.

Have somebody done something like this before? Some hints of plugins or possible ways to achieve it?

Thank you!
Fer