This fiery piano-pounder did more than popularize his chosen instrument in early rock 'n' roll. His brazen barroom delivery paved the way for country rebels like Hank Williams Jr., psychobilly oddballs like Mojo Nixon, and heartland rockers like Bruce Springsteen and Bon Jovi. Even pop stars have looked to his painfully frank lyrics, whether it's Justin Timberlake's self-medication salute “Drink You Away” or Bruno Mars' romantically boozy “Marry You.”