For a time, my FAS wore '1701-D' as a registration, but I thought it was a bit predictable, so now all my ship IDs are an extension of the purpose or name of the ship, so for example my Orca ID is 'GTUTHR' (Get you there), while the name of it is also copyright dubious 'Midnight Express'. My FAS as my main PvP ship reg is 'GTNGUD' (getting gud), my Python, Black Betty's reg is a reference to the song and just says 'WOAH!', etc, etc.
I love this stuff, trying to come up with clever names and related IDs. Sad really. lol.
edit: Doh, I just now read the thread title properly. NPC names... I can't think of any really blatant ones, but I'll keep my eyes open from now on.