Actually an iPod connected to a cassette adapter doesn't sound too bad - the quality is MUCH better than you would get if you were using an FM transmitter such as an iTrip (which is prone to interference). I'd choose the iPod simply because it's the ultimate road trip accessory - I listen to podcasts (MP3 programs such as radio shows automatically downloaded into the iPod) almost everyday. And if you get a new iPod, video playback capability is built in at no additional cost - with a generic video cable, you can just attach the iPod directly to an LCD monitor and play back movies directly off the iPod's hard disk (or if you are so inclined, you can just pump the audio out of your car stereo and settle for the iPod's 2.5-inch screen).