My home systems use Tolkien names, which while by no means an original idea, has the benefit that they will never run out, especially if you've read The Silmari

My home systems use Tolkien names, which while by no means an original idea, has the benefit that they will never run out, especially if you've read The Silmarillion. At work, the names are all music-related. I didn't start this one, but I carried it on after the admin who started it left. This also works well, aside from coworkers complaining that they can't remember how to spell 'staccato'.