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From Categorism.com
A temporary page for those it concerns.
Third video is: https://www.ted.com/talks/moriba_jah_what_if_every_satellite_suddenly_disappeared
Second video was: https://www.ted.com/talks/adrian_paenza_how_folding_paper_can_get_you_to_the_moon
First video was: https://www.ted.com/talks/evan_zodl_the_unexpected_math_of_origami