eBay...Cayenne flip key.
http://www.ebay.com/itm/181576884889
I did this last year. Didn't work out. The fold away blade is nice when it's in your pocket, but the fob/car portion is too long and awkward in the 986. I was always worried that I'd hit it and break my ignition, especially when using the turn lever.
Of course, if you want the electronics to work, that's a whole different ballgame.