even simpler since it already comes with usb instead of 2mm

http://www.bike2power.com/products/

Seems like it would be an even better system if there was storage inbetween, like a DC-8 strapped on handlebar between dynamo regulator and phone so the dynamo charges the dc-16 and the dc-16 charges your phone constantly anyway. I suppose eventually you would need to charge the dc-16 manually, but it should go for a long time.