In Back to the Future, Michael J. Fox’s character Marty McFly is also wearing a calculator watch. After analyzing the DVD and some catalogs from the period, we have high confidence that the time-travelling slacker is sporting a Casio CA-50.
“The Feynman point is the sequence of six 9s which begins at the 762nd decimal place of the base 10 representation of π. It is named after physicist Richard Feynman, who once stated during a lecture he would like to memorize the digits of π until that point, so he could recite them and quip “nine nine nine nine nine nine and so on.”