A fellow player played 'Tfolnevar' (silent T) in a 2e Domain of Dread campaign.
Another player has such a hard time coming up with names, that he's been leashed with the Gygaxian-formed 'Kram' a few times.
Another player, when asked her name in an email, replied, "Not sure yet", so was named Notsu Reyet.
Not necessarily a bad name, but in one campaign, two of the players (dating at the time) made characters independantly, but both named their elves 'Lia', although they did have different last names.
'Knil' and 'Nada' were played by two players playing siblings who replied "none" when asked for names during character creation.
Another used the name 'Joilet' (I think from one of those old AD&D cards) for a paladin, but had such bad penmanship that it looked like 'Toilet' on his sheet, so much potty humor was derived from his knight in porcelain armor...