What do you mean legit? backcounting and ST are totally legal if you use your head. For backcounting: Professional Blackjack, Blackjack attack are among my favorites, For shuffle tracking: Shuffle-Tracker Cookbook (is great for learning the actual machinery of ST, but I am not too fond of his betting strategies), (Dead link: http://games.groups.yahoo.com/group/blackjackcardcounterscafe/message/22118) great post by Alienated that discusses NRS