One of the previous hosts of NBC’s Tonight Show, albeit briefly, is Conan O’Brien, who tonight provides a special edition of Conan that would have been eminently Tonight Show-worthy. To honor the death last week of pioneering TV comedian Sid Caesar, O’Brien has scrubbed his originally planned show for tonight to turn over most of it to a visit, and conversation, with Mel Brooks, who began writing for Caesar in the late 1940s, even before they both worked on that landmark masterpiece of early comedy genius, NBC’s Your Show of Shows. O’Brien is not only an appreciative student of Mel Brooks’ humor, but he’s covered some of this conversational ground before: Mel was one of O’Brien’s early, and most entertaining, guests on O’Brien’s no-audience Internet “talk show,” Serious Jibber-Jabber. Giving the wonderful Mel Brooks, with his amazing memory and unparalleled knack for storytelling, a chance to salute his old friend on Conan, is a perfect use of late-night TV. Good for you, Conan. Good for you, too, Mel.