Griffin Technology Aircurve Play for Iphone 4
AirCurve Play makes the speaker of your iPhone 4 sound 10 decibels louder, and it works without batteries or cables. Just slip your iPhone into AirCurve's rubber dock gasket, and your iPhone 4 becomes the perfect portable audio/video conference phone, video viewer and game platform. AirCurve is a cleverly designed acoustic amplifier that collects the sound from the built-in speaker of your iPhone, amplifies it in a coiled waveguide within the base, and projects it into the room. Though AirCurve, itself, uses no power, it features a pass-through slot that allows you to insert your own cable so you can charge and sync while you listen. And AirCurve's transparent polycarbonate body lets you appreciate the graceful curves inside that do all the work.