Late Night: Jimmy Fallon and Will Smith get jazzy with it Will Smith stopped by "Late Night" on Thursday to plug his latest movie, "Men in Black 3" -- perhaps you've heard of it -- but little did he know he'd uncover some family secrets, too. Jimmy Fallon explained that studio 6B, where "Late Night" is taped, has a long and colorful broadcasting history, dating back to the early days of television and radio. The space was even home to a radio show hosted by their "grandfathers," Will "Sunnyside" Smith and James "Fatty Monroe" Fallon. The jazz duo had clearly influenced Smith's musical career, Fallon suggested. As evidence, he played "long-lost" black-and-white footage of grandpas Smith and Fallon performing ragtime versions of "Parents Just Don't Understand" and "Gettin' Jiggy With It." As with all of Fallon's musical parodies, this one was spot-on, from Fallon's slightly nasal vocals to the exclamation -- "Hot peanuts!" -- with which Smith ended each of the songs. Quick, someone get these two on "Boardwalk Empire." "I'm Khloe Kardashian's father," says Tracy Morgan Conan O'Brien and David Letterman take shots at Jay Leno