Sold in white or black versions, Simplism's Remote Controller for iPod ($20, aka Remote Controller 3 Buttons) adds a three-button remote control to any pair of headphones you already own, enabling them to be used with the third-generation iPod shuffle, as well as offering volume and play/pause controls for the 2008-2009 iPod classic, iPod nano 4G/5G, iPod touch 2G/3G, and iPhone 3GS. The boxy remote does not include an integrated microphone,…