Conan O’Brien was back on his former stomping grounds at Universal Studios Saturday night, bringing his Legally Prohibited to be Funny on TV tour to the Gibson Amphitheatre, some 400 yards from his old Tonight Show stage. “This is my first time back at Universal Studios since I lost my job,” O’Brien told the crowd, igniting a wave of boos directed toward NBC. “Don’t boo too loudly. If you listen very carefully, you can hear bad ideas being greenlit.”

It is not clear yet where O’Brien’s new talk show for TBS, announced as the comedian was kicking off his tour two weeks ago, will be housed. One possibility is TBS’ sibling studio Warner Bros TV where O’Brien’s company now will be based, along with Sunset Gower and even the vacant stage for NBC’s Tonight Show with Conan O’Brien built for $50M. There are ramblings on the Warners lot that Stage 16 there is being eyed for Conan.

Among the surprises in the Los Angeles show, Aziz Ansari, Jonah Hill, Jon Hamm and Jack MacBrayer took turns pulling the handle on the Walker, Texas Ranger lever. “I’m just glad I’m not one of the guys who works for NBC pulling the handle,” Mad Men star Hamm quipped, a reference to Parks & Recreation co-star Ansari and 30 Rock’s MacBrayer. Jim Carrey as Superman  joined O’Brien on stage for a duet of Five for Fighting’s Superman (It’s Not Easy).

Before the show, WME, which reps O’Brien, threw a bash for the comedian who made an appearance just before hitting the stage.

O’Brien will be back at the Gibson Amphitheatre tonight before heading to San Diego. In addition to the gig at the Gibson, O’Brien also will perform at Radio City Music Hall in New York, which is just a stone’s throw away from the NBC’s headquarters and his old Late Night stage. Sources tell me the proximity to NBC was not the driving factor in the venue selection for Los Angeles and New York but O’Brien must be enjoying the irony.

With additional reporting from inside the Gibson by MTV.com.

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