SIM Card Earrings
SIM cards are removable "smart cards" in phones that securely stores the key identify a mobile phone as under the service of a particular company (T-Mobile or Cingular in the US). In essence, a SIM card allows one to buy a mobile phone and keep it if they decide to switch plan providers.
That said, I'm all for recycling and reusing materials, so if you have a few SIM cards laying around because you change plans back and forth between Cingular and T-Mobile, then here's a way to make them into awesome earrings: How To Make SIM Card Earrings.