Excerpt: Family Friendly Gaming continues to branch out, grow and diversify. We have decided to do our first ever cell phone peripheral review. The Cardo S-640 revolutionalizes bluetooth by giving the user a clip on, and ear piece. One of the most interesting aspects of this is the ear piece can be used like a microphone (editor: as long as the sound is turned up and stays close enough to the ear). The best way to think about that is a compact speaker phone.