We often find we end up assigning everyobody a name after a while anyway. It's something of a tradition in Japan, and an honour to be accepted and given a name. It's how I ended up with Shiro Tora (though here I am The Guv of course!).
It's fun, it's what they do in The Matrix, choosing their "real" name over their "assigned" name, and what the X Men did.