Fiio’s latest E5 headphone amplifier clearly looks like the latest iPod shuffle. They really complement each other when used together.
The Amplifier reportedly puts out 150mW at 160ohms with a rate distortion of less than 0.009% at 10mW. It runs on a rechargeable battery, chargeable via USB. Keeps working up to 20hr with full juice in the battery. At a price of $20, it is not that hard on pockets either.