Another idea I had for Display names was to have a column in w3t_Users that would store all display names 'permenantly', then list them on the user's profile. So if you looked at the user's profile, it would show any different display names they'd used in the past. I'd like to make it searchable as well, so that if someone wants to know if user "A" has been around in awhile, they could search for user "A"'s posts and it would show them that user "A" is now being seen as user "B", with a link to B's profile or posts.
It sounded fairly simple in my head until I typed it out.