I have an iPod media cable which connects to the RCA inputs and lets me play my podcasts and music on the drive home each day (roughly 45 minutes to an hour M-Th, 1-2 hours on Fridays). While it works great, there is a trick to making it work:
When using the media cable with my iPod (classic type), you have to click "Video", then "Video Settings" and set "TV Out" to "Yes". That's not all. Even though that usually works to play video podcasts and movies (the van has a built-in DVD viewer on the ceiling), music doesn't normally respect that setting and automatically stream out through the media cable. You have to first play at least a few seconds of a video clip (podcast, movie) and then go back into the music library to play music or audio podcasts. Kind of weird but that's how it works. It seems to sense the type of media being played before it actually streams data through the media cable.
Life is good. I get to listen to podcasts like "No Agenda", DiggNation, "Daily Source Code","Cranky Geeks", and "This Week in Tech". Life is good.