My 'Christmas' tradition is quietly reminding those who get in my face while I'm out and about that not everyone is Christian!
I loathe the traditional holidays. Why? It's a tossup whether I will get the 'Merry Christmas' ad nauseam or who-knows-what-else; lawsuits happen over this question! SeaTac Airport had to pull down all the decorations last year because someone got toasted that there wasn't a menorah up as well, and threatened to sue. This year it's totally nondemoninational trees with snow and icicles, and guess what? There's a threatened lawsuit.
I have gotten militant over this some years; when I get questioned, it's always 'not Christian, not Jewish, not Muslim, not atheist, but not telling you what I am, thank you.' Which, in some cities, can get you a pretty scary response. Bah on their little religious narrow-mindedness. There are lots of religions out there, including none at all (for all the atheists out there).
About the twentieth time someone asks me what I'm doing for Christmas (while buying groceries), I start thinking of responses guaranteed to shock and annoy; what I WILL be doing is just the same as the day before, and the day after: whatever I want, assuming it's open. Christmas is so not a holiday at my house.
There are two things one can do in just about any city in the world, which are going to the nearest cinema and/or going to a good ethnic (usually Chinese) restaurant. Anything else: too bad. Don't like Chinese or no film interests you? Might as well stay home, but don't turn on the radio or the tv, it's all reruns of the same trite... ahem, time to get off the soapbox...

My favorite Christmas tradition: seeing it go away in the rear-view mirror...