PROBLEM: You want to play the music on your iPod (or other digital jukebox) in the car, where you have a factory head unit with an AUX that only talks to CD changers — and you live in an urban area where all FM frequencies are taken, so those stupid FM transmitter solutions simply don't work at all.

SOLUTION: The Aux2Car from Peripheral Electronics. You purchase this sucker, plus a customized harness that connects it to the head unit in your particular vehicle. As far as your car stereo is concerned, this sucker is a CD changer, but of course, it's not. It just talks to whatever device you plug into it.

The whole shebang cost me about a hundred bucks (great prices on eBay...), and it took about an hour to install. The installation procedure includes the setting of DIP switches, which I hadn't encountered for years; I felt taken back in time in a very happy way. And now, there's a plug in my car that fits right into the line out of my MP3 player (a 20GB Rockbox-ed iRiver IHP-120 — soon to be replaced by an 80GB iPod, as soon as Rockbox runs on those), or the headphone jack of my Treo 700P cell phone, which is sporting a 4GB card full of tunes these days. Digital music in the car, at long last! HUZZAH!