From Episode 18 of Bodacious Space Pirates, being used as a platform by Ai, who is clearly too short to reach the ships wheel without it. They aren’t just regular Mikan either, they’re Uchu (Space) Mikan. What, precisely, makes them Space Mikan as opposed to Regular Mikan is, I fear, going to remain the shows greatest mystery until it’s conclusion.

It is also unclear as to whether the Mikan contained within the box are as bodacious as the pirates who stand upon them (though, saying that, I rather suspect that Mr. Show fulfils a large percentage of the shows quotient of bodaciousness, rather than the pirates themselves).