Ambigrams are forms that look the same when rotated or flipped, like the image below:
One day, Trinity College, Cambridge, undergrad Adam P Goucher was wondering whether "it would be possible to write a true statement in first-order logic together with logical conjunctions and arithmetic operations, which also functions as an ambigram" when flipped upside down.
There are, of course, simple and trivial equations like 1 + 1 = 1 + 1, but Adam found non-trivial ones:
61 - (8 + 8 + 8 + 8 + 8) = (8 + 8 + 8 + 8 + 8) - 19
and
98 x 99 – (609 + 6969 + 111) = (111 + 6969 + 609) – 66 x 86
Super neat! Link - via The Guardian
Question is, is that a stupid or clever math trick? To which we have the answer: Why not both?
Clever/Stupid
Ambigram T-Shirt
Heh, been waiting to use that reflective ambigram Clever/Stupid T-Shirt from the NeatoShop for a while!