This was how we snuck/sneaked an electronic game into class in 1982 - and now you can bring one into your business meetings because Casio has reissued their Number Invaders game calculator. UPDATE - In the game if you shoot two numbers in succession that add up to 10 then the invader appears - the invader is worth more points. The last two minutes are my usual outro. If the proportion of new content to existing outro is unacceptable to you - here is an alternative version with a quicker outro. ;-) https://youtu.be/FOrH6RnPqd0 - or you could always just stop playback of this video when you want to stop watching. When the fun stops, stop.