The famous Square-Circle trick. I’ve used this at so many events and whenever people see it, they always want one!
Hold up a metal circle and display it openly, front and back.
With a flick of the wrist, it turns into a square! This is visually stunning and regulsarly draws a gasp whenever it is performed.
Easy to do with just a few minutes practice.
The Squircle holds a curious claim to fame – it is the only thing that has ever won the coveted ‘Best talk’ prize at the annual UK Big Maths Jam. (This is not quite as impressive as it sounds: the prize was awarded in the inaugural year, and quite rightly the prize has not been offered or awarded since, in the spirit of inclusivity).
I have managed to import a limited number from the United States – once they’re gone, they’re gone! Here’s a short demo of how insanely good it looks!