Idea for an activity: in trios, one player is the couch potato, the other two are actors in a TV show. The actors improvise a dialogue. At any time, the couch potato can say, "mute!" as if hitting the mute button on a remote control. When s/he does that, the players continue their dialogue without any sound.
The players have to pay attention so that when the couch potato turns off the mute, they have something to say.
Variation: the couch potato can change the channel by calling out, "channel two!" The players then switch to a different type of show (from Drama to News, e.g.). It is up to the players to choose the type of show and, using the "yes, and" approach communicate it to their partners.