21/8/09, Gilded Balloon (Edinburgh Fringe)
A magic and illusions show by a couple of student conjurors and mathematicians, Morgan and West, with Victorian whiskers and lots of audience participation.
Lots of "how did they do that?" tricks with packs of cards, numbers in envelopes etc etc. I had some idea how they did the "crush the paper cup with the nail hidden underneath it" trick (the one who wasn't blindfolded made sure it was always the one on the left) and possibly some idea of how the fat one got a "magic number square" out of two numbers contributed by the audience, 21 and 58 -- he wrote down 19 instead of 58, then at the end of the show produced a magic number square in which each 4 x 4 row added up to 58, invited the woman who'd first suggested 58 to extract a sheet of paper with that number written on it from an envelope stuck to the back wall, and got someone else from the audience to add up random numbers which produced the day's date (21/08/2009 -- which also just happens to add up to 58. So she must have been a stooge, right? Except we'd seen her in the queue beforehand with her husband and the kids...)
But I've no idea how they did most of it, which must be a mark of success. Highly entertaining.