Dave talks about the $270 he spent on an Inline Patch from JK Audio a few years ago has not produced better results than the $25 a year he pays for SkypeOut .
Dave also has tried 2 FM transmitters for either the iPod or a portable player. The Griffin transmitter for the iPod had no volume control, and it was really quiet. This results in your cranking up your volume in your car. In the end, it was noisey, and not a great solution.
If you saw someone who would obviously enjoy your podcast, do you have a business card, a sample CD, etc available RIGHT NOW to hand this potential listener?