Found this little gem on a blog called AppAdvice. It's a little tiny iPod/iPhone dock that plugs into the USB plug on your normal charger to make the most minimal dock possible! one downside is that it only works on plugs that are "face up" so it won't work on some of those distro boxes that have the sideways edisons. Other than that, the Blue Lounge Mini Dock seems like the perfect solution to having to carry around the dock cable just for your charger.
You can pick it up on Blue Lounge's website for $20