Whenever somebody's playing one of the games on this site, it's on this TV. Turn it on and flip channels. They can't see or hear you. They do get a little ON AIR tag on their screen that counts how many of you are watching.
How it works. A game goes on the air once somebody starts playing it on a computer or TV (never from a phone). Watchers get the game's screen and its sound, sent straight from that computer, the same way the phones talk to it. Menus show up as PLEASE STAND BY, and the spoken voices don't come through. Nothing else in the room ever does.
Playing and don't want an audience? Click the ON AIR tag in the corner of the game. It goes off the air and stays off on that computer until you click it again. Up to 6 people can watch one game at a time, since every one of them takes a little of that computer's internet.