I have reached the end of the internet searching for this. It seems like a product like this must be made by *someone*, it's so obvious. But, I cannot find it. I want a cable that plugs into the 30-pin dock on my iPhone 3G. Coming out I want USB for charging and RCA audio for output to a stereo system (namely, my Alpine head unit) Currently in my car I have a Griffin Powerjolt that goes into the 30-pin, and a Monster 3.5mm > RCA. This works fine, but I'm tired of having two cables come out of my iPhone. Anyone?