We're about to boldly go ... where no talk show host and guest have gone before. It's dance ... the final frontier. William Shatner showed up on 'Jimmy Kimmel Live' (weeknights, 12AM ET on ABC). During the interview, Kimmel suggested that Shatner would make a ideal contestant on 'Dancing With the Stars.'

But Shatner poo-pooed the idea. He pointed out that the show lasts forever, and he's not the youngest guy anymore. "They want four months of your time!" he said.

William is no coward -- after all, he's the original James T. Kirk, heroic captain of the USS Enterprise. Shatner just is too busy to take part in 'DWTS.' Still, in order to prove his dancing bravery, the actor decided to teach Jimmy how to do the waltz. But first, there was a tiny matter to clear up. Which of them would "lead' in the dance? That is, who would be "the man"?

Obviously, the "man" was going to be Mr. William Shatner! Which put Kimmel in the more unfortunate role of, well, "the woman." But Jimmy's woes weren't over yet. Shatner took the host on a brief waltz around the studio, but quickly criticized Kimmel's dancing posture. The actor told Jimmy to stay "erect." "You remember what it's like to stay 'erect,' right?" But at this point, Kimmel couldn't take it anymore -- and started cracking up.