I know this is an on going thing 'Who is the Stig?', well a new name to add - Russ Swift (Professional Stunt driver). I meet the guy a while back and he definitely has the skills involved. Also Ben Collins (ex-Stig) has admitted to there being more than one Stig and Damon Hill has been one of them.
P.S. I think you can include some current F1 drivers in that list.