Justice Kagan had quite the memorable quote in Schwarzenneger v. EMA:

JUSTICE KAGAN: It’s a candidate, meaning, yes, a reasonable jury could find that Mortal Combat [sic], which is an iconic game, which I am sure half of the clerks who work for us spend considerable amounts of time in their adolescence playing.
JUSTICE SCALIA: I don’t know what she’s talk[ing] about.

I guess Justice Scalia’s clerks never played Mortal Kombat. Finish him!

Justice Sotomayor showed that she is a bit of a Star Trek fan, asking about torturing Vulcans.

JUSTICE SOTOMAYOR: Would a video game that portrayed a Vulcan as opposed to a human being, being maimed and tortured, would that be covered by the act?