A friend in a 997 does have a spare collapsible wheel that I think he carried over from his 996.
He has to carry it in the rear seat when he goes on holidays!!

and I'm not aware if he's ever had to use it ever.
I'm also not aware if it will fit the Turbo either with the larger brakes?
A few of us have invested in the silverline tyre repair kit
http://www.silverlinetools.com/en-GB/Pr ... eel/380421 which a 991 owner used to get from Switzerland back home! where he replaced the tyre.
As Sean mentioned the gunk can work on smaller punctures and splits, however the silverline is a good option if you are looking at a larger hole from a bolt etc..
It also saves the mess from the gunk
