The moment they're all named, musical chairs is played and the users want the name of their hated predecessor expunged and their own name put in place. Then you have to go around and change the drive/printer assignments all over the place, and two weeks later it's musical chairs again..
I use animal names (Bear, Badger, Gerbil etc), trees (Oak, Walnut, Maple, etc.), or fish (Trout, Pike, Walleye, etc.) or some combination (perhaps servers are animals, users are trees). People seem to have little trouble remembering these names and where they are.
When the boss insists on having his computer named after himself, two months later the shipping department has a computer with the bosses name and he wonders why he can't name his new computer after himself.
Of course I deal with small businesses (3 to 30 computers) - this probably wouldn't work in a large installation without some prefixes.