During his appearance on the show to promote NBC's Revolution, on which he's a producer, Abrams told O'Brien that he had a special presentation to bring to the show.
The pair set up the clip, with Abrams explaining that he had wanted to bring something exclusive for O'Brien but that the studio wasn't willing to let him bring anything longer than three frames. He explained that what you can see below is actually Spock, who "for reasons that you have to see the film to understand, is in a volcano in this crazy suit."
"Spock seems kind of different to me now. It's not like classic Spock," joked O'Brien's sidekick Andy Richter.
The film is due in theaters in May 2013, and will likely see an official trailer release soon.