6. Warren Zevon
Warren Zevon is so much more than that guy who sang "Werewolves of London." Anyone that doesn't know his catalog should put on Excitable Boy, Bad Luck Streak in Dancing School and Stand in the Fire and prepare to be amazed. He was one of the great songwriters of his era and tunes like "Mohammed's Radio," "Roland the Headless Thompson Gunner" and "Accidentally Like a Martyr" only improve with age. He battled all sorts of addictions and never got the acclaim he deserved until shortly before he died of lung cancer in 2003. It may take a few more years, but he'll make it into the Hall of Fame one day.