Boards
Imagine if you went to see a comedian
and everytime he told a joke there was a little pause and the audience have to press 'Yes' or 'No' on a little touch-screen infront of them to declare whether they got the joke or not. "Okay guys if you now look at the screen infront of you. By the way, it is IMPERATIVE that your answer is given as true to the time that the screen lit up infront of you. If for example you suddenly get the joke right before you're about to press 'No' then DO NOT under any circumstances change your answer to 'Yes'. It is HIGHLY IMPORTANT that you DO NOT change your answer guys."
There's a projection screen behind him and the results for each joke appear as a pie chart with different colours everytime.