Kokopelli

Yesterday I've unlocked my wife's '94 Golf and then put the key in the ignition and the radio came on as it does. However, for some reason I couldn't turn the key in the ignition. Finally found out that i've been using the 944 key. It's almost identical to the Golf's key. The Golf key opens the 944 as well.

Techno Duck

I have read before that the tumblers on the 944's can become so worn, that other 944 keys will open, and in some cases start other 944's.

Porsche-O-Phile

If you're looking for one of those "impossible to find" alarm key blanks (they are no longer available through the dealership!) use a Saab one. Works perfectly.

Epic2112

I realized the same thing working on my friend's 93 Jetta, although I tried it on purpose.