Would Will Hunting use OS X? He might now:

TeX is a typesetting standard that, among other things, allows you to typeset complex math formulas. One flavour of Tex is LaTeX, for which LaTeXiT serves as a front-end on Mac OS X. Using LaTeXiT, one can drag and drop complex math formulas to a number of apps — Pages, Keynote and TextEdit, to name a few.

If March 5^th is 35, then 35×35 = 1225 means that March 5^th squared is December 25^th, so March 5^th is the square root of Christmas!