Ampli-phone

And you may ask "how much more green...". Ampli-phone uses pure acoustics to boost the iPhones volume by 10db but the horn is big enough to produce good low frequencies (200 - 35k Hz). Get a better price $20 at Macworld or www.ampli-phone.com. Ask the guys about sustainable manufacturing.
I really like the idea of skipping the need for batteries.

The idea is the same as the Griffin AirCurve (see below), but much larger. We'll have to watch the gadget testers to see which features are best.