Robyn, ever vigilant, points me to this intriguing suggestion for a new holiday, a purely secular one: Newtonmass. My favorite bit:

With gifts exchanged, everyone begins the most important Newtonmas tradition---procrastination. Now that you have new sources of knowledge, it's time to get busy not absorbing their contents. Eat a big meal, take a nap, talk with friends and family. Just do anything but be productive.

This is all well and good, but I would like to nominate Galileo if we're going to get serious about this. Galileomass (or Leomass) has a lot going for it.

First, the plain facts (via Wikipedia):

Galileo Galilei (15 February 1564 – 8 January 1642) was an Italian physicist, astronomer, and philosopher who was closely associated with the scientific revolution. His achievements include improvements to the telescope, a variety of astronomical observations, and effective support for Copernicanism. According to Stephen Hawking, Galileo has probably contributed more to the creation of the modern natural sciences than anybody else. He has been referred to as the "father of modern astronomy," as the "father of modern physics", and as the "father of science". The work of Galileo is considered to be a significant break from that of Aristotle.

1. For a big holiday, you need a figurehead with a memorable physical presence. And the beard doesn't hurt either.

2. A catch phrase is crucial. Ho ho ho is fine and dandy (nobody is talking here about giving up Christmas, please remember), but

eppure' si muove

Now, that resonates. The Papal Office forced Galileo (on pain of death) to recant his silly notion that the earth revolved around the sun. Galileo lived on to fight another day, but he did mutter under his breath: nevertheless, it moves.

A stubborn and cranky and intellectually superior figurehead: what secular humanist could resist? Not me.

3. Please note that Galileo was in fact Italian. Nobody does a party better.

My suggestions for this annual celebration:

• No gifts.
• No decorations (with the possible exception of a banner embroidered eppur' si muove)
• Friends and family you get along with only.
• Lots of good food and drink around a big table while kids run yelling through the house and dogs bark and your Aunt Rita tells the story of how when she was a young thing just starting her first job in Manhattan she met Errol Flynn, and what he said about her eyes. Also required: lots of table thumping during political discussions. Finally the master of ceremonies gets up and reads excerpts from creationist tracts, pausing now and then so that everybody can yell, all together:

  EPPUR' SI MUOVE!

• Then everybody helps with the dishes and when the kitchen is spotless and tidy, they all go home.