Things I Never Knew, part 1

I've often wondered (because I am sad like that) how film-makers come up with the names of their characters, particularly in action movies. I wondered if there was some focus group coming up with tough, macho style names to attach to the latest Van Dammage feature, or whether it's picked at random from the phone book.

Well, apparently, to legally use a name in a film, there either have to be no examples of that name in the US national phone directory, or at least five examples. I assume this only applies to American films.