18. Howard Stern
Age has mellowed Howard Stern in the best way possible. At 59, he knows he doesn't need to waste time lashing out at perceived rivals or proving his shock-jock credentials by interviewing an endless parade of porn stars and freaks. Now in his seventh year on Sirius XM, he does revealing and hilarious interviews with guests ranging from Revenge of the Nerds star Robert Carradine to Lady Gaga to J.B. Smoove. More importantly, he's painfully honest about his own life, sharing everything from his failed attempt to push his parents into a rest home to his newfound interest in babysitter-themed pornography. Can you imagine Letterman or Leno going there?