Well, maybe it's not an iPhone per se, but if this rumor were to hold true we could see an Apple device with similar technology in upcoming Mercedes vehicles.

This rumor comes to us courtesy of a German magazine called FOCUS. They recently reported that the automotive company will equip their vehicles with “a Navigation System from Apple’s design-laboratories starting in 2009. After six months other car manufacturers shall follow”

I'm not sure just how much faith I would put into this rumor. Apple hasn't even included GPS in their iPhone, why would they be developing a full navigation system? Then again, Apple has already invaded your office and your living room, why not tackle your car too?

Mercedes to get Apple-designed GPS in 2009? [via SlashGear]