In case you don't drive a late-model BMW, another option for connecting an iPod to a car is the Dension ICELink. Through a set of modular components, the ICELink will be able to connect 1st/2nd generation iPods, 3rd generation iPods and even iPod Minis to a wide variety of stock and after-market car stereos. Unfortunately availability seems to be an issue a number of modules are sold out or not yet released. iPodlounge has a review of one ICELink install.