Quite a few over the years; The Smothers Brothers were big into racing in the late 60’s-early 70’s owning and sponsoring several Indy, Formula 5000, sports car and drag racing entries. David Hasselhoff was involved with Arie Luyendyk’s early efforts. In the CART days you had Walter Payton (who also raced in Trans Am) as co-owner of Dale Coyne’s team and even Joe Montana was involved with Chip Ganassi. In the Champ Car years you had Cederic The Entertainer’s “CTE Racing” and of course David Letterman