Megaphone BY en&is

Passive Amplifier for iphone made of ceramic. The form is designed to amplify and optimize the best sound output. The amplifier is based on a thin wooden frame that allows the object to float off the table. This, in order to increase the vibration of the object and to optimize the emission of sound. Designed for the iPhone is perfect for listening music without headphones, for audio conference to hear the person on the phone as live voice.
Compatible with iPhone 2G, iPhone 3G, iPhone 3GS, iPhone 4, iPhone 4S, iPod Touch (from the second generation onwards) with case.
source: enandis.com