To go along with your leftover turkey sandwiches another potpourri of mathy schtuff(ing) to choose from:
1) First, if you missed it, this nice little demonstration of the Pythagorean Theorem using water as a tool (it's not a technical or real "proof" but a very good 'visual' effect):
2) If you missed NPR's "This American Life" last week (…and you ought NEVER miss TAL), the prologue to the week's stories dealt with Frank Nelson Cole, who back in 1903 proved that a 21-digit number which Marin Mersenne had identified as prime centuries earlier, was in fact a composite number… worth a listen (to at least the opening prologue):
3) Not exactly math, but an interesting British piece on wartime (WWII) cryptography and pigeons flying secret codes; a recently found dead pigeon from the period has a small sheet of code attached to a leg that has stumped modern-day code-breakers:
"...without fresh information this pigeon may well have taken its secret to the grave." The BBC is actively asking for suggestions to decipher the message.
[ADDENDUM: great followup on this story from James Grime here:
4) Finally, a good discussion of Bayesian versus frequentist "inference" here, with plenty of comments: