Long ago I informed you that cassette adapters, while low-tech, are infinitely better than FM transmitters as a way to get sound from your MP3 player to your car stereo (of course if you have line line in or similar then it’s a non-issue)
Griffin has taken the cassette adapter to the next level, allowing you to control an iPod through the play, pause, and forward/rewind controls on the tape deck. I guess it detects rotation (or not) of the spindles, and commands the iPod accordingly.
Quite cool, although I can imagine one possible problem: my particular car cassette deck (and I presume others) has auto-aligning heads, meaning after each FF or RWD command, the heads seem to land in a different place. Getting the best sound from my current cassette adapter requires a hit-and-miss method of hitting FF then PLAY multiple times until the heads are just right. This would obviously suck with the Griffin adapter.