Today, we raise a glass to one of the funniest men on late night TV: Jimmy Fallon. The newly minted Tonight Show host celebrates a major milestone, ringing in his 40th birthday in the midst of a super-successful career that boasts an Emmy win for his work on Saturday Night Live and a Grammy nod for his comedy album. The SNL alum even starred as InStyle’s Man of Style back in 2004 when he was merely 30—how's that for a flashback? "I've had many fashion disasters," he admitted to us. "I'm glad I had my sister ... someone who'll tell you when you're lame. Like when you're getting ready to go to school, and you're like, 'This bandanna is cool, man!'" Sound advice!