This a bit old but the dude MAR 28 2008
This a bit old but the dude that runs the stylish cameron i/o site (who is coincidentially named Cameron) built a trumpet-like bell for the iPhone out of a used toilet paper tube.
I wanted to listen to my music in the shower but the iPhone's speaker would get lost in the noise from the shower. So I directed the iPhone's audio straight towards me. Worked pretty well. Just ask my neighbors.