Just saw this -- Alex Zanardi(ex F1 driver and ex Champion in the Champ car series) who lost both legs in a racing accident in 2001 may attempt a return to racing in sedans.
Earlier this year in a publicity drive he drove the "final 13 laps" (of the race where he had his accident) in a specially equipped car -- and reportedly drove fast enough to be in the race (190 + mph).
He is an amazing guy -- seems indomitable.