This is a trivial and small addon which adds a line to the mouseover tooltip for any player or NPC telling you the name of their target. It's most useful if you want to see if that guy standing next to you is inspecting you with having to target him first so that he doesn't know that you know he's checking you out :D

Hey, turns out (thanks to Wmambalamb) that there IS a use for this beyond vanity -- tanks can use it to quickly ensure that mobs are one the right target so they can decide whether to take action without having to lose their current target! Thanks Wmambalamb for making me feel less ashamed for writing this :D