how about a guestmap? you know, basically a map of the world where users can post their locations and maybe a little note for others to see where everyone is from on the forum. the map would be of course integrated into the forum as far as username/profile, maybe even coordinating the user's location to automatically place their location on the guestmap without having the user do it manually.
i can get a basic idea of how it would work.. an imagemap for using the world map would be needed most definitely.
to get an idea of what i'm talking about, bravenet has a
free guestmap service (although not vb integrated, of course).