Blizzard authenticators worn round a gamers neck.
This item would be carried around with a laptop and so he/she could show off the amount of accounts he/she owns and the 'gear' that he owns
Guy1: Dude! Thats some awsome nerd bling!
Guy2: oh why thank you, ill show you my Tauren Arcane Rogue if you want! You will be amazed by my uber skills!