From Carrie Underwood to Taylor Hicks to that kid who lived in his car (remember him?) -- the tryouts that were so good, even Simon couldn't dismiss 'em
15. David Cook, ''Livin' on a Prayer'' (Season 7)
Okay, so the season 7 champ was sporting a goofy fauxhawk and unfortunate red highlights when he busted out some Bon Jovi in a nondescript conference room in Omaha, NE. But close your eyes and listen to the unexpected choices Cookie makes with the song's tempo and melody, and you'll get a glimpse of the distinctive, daring re-arranger who inspired a nation of speed-dialers and changed the Idol game forever, and for the better.