Let's get this clear: I respect people's religious rights to the hilt, and will happily beat round the head any idiot who thinks that Christmas is bad per se. However, the whole central concept of Christmas - a baby being born after artificial insemination by a deity and with angels and astronomically-implausible phenomena hanging overhead - is very much against my personal reality-based ideals. Quite frankly it's daft, and it's increasingly the case that self-oblivious daftness bugs the
Of course I'm not the only person who feels like this. Many atheists are irritated by being forced into association with someone else's festival, so let's look at what they do.
Approach 1: Commercialism is the reason for the season
The first approach amongst atheists is to unhesitatingly accept all the trappings of Christmas, but in addition to accept something that Christians have been complaining about for years: that Christmas seems to be getting less oriented around Christianity every year. The result is a sense of smug satisfaction without having to worry about whether it's acceptable to break out the Christmas Pudding.
On a side-note, I'd like to ask those complaining Christians: who do you think you're kidding? If you're going to "borrow" random holidays off of older religions, and at a time of year where your story couldn't possibly have happened to boot, you have very little grounds to grumble when said holidays are repurloined. Honestly, it's worse than Disney ripping off random fairytales and then whining about copyright not being strict enough.
Rant over, next approach.
Approach 2: Cthulhu is the reason for the season
Proponent: PZ Myers
The next methodology takes the above idea about Christmas not being Christian one step further, by picking a completely new name for an event that just happens to roughly coincide with the better-known festival. Examples are Cephalopodmas, wintereenmas, solstice, festivus, ramahanukwanzmas and probably dozens of others.
Many of these provide a wonderful biting commentary on various aspects of Christmas, not least its complete and unconscionable lack of squid, but to be quite frank they all sound quite, quite lame. Not to mention as fake as a tin shilling.
Approach 3: Axial Tilt is the reason for the season
Proponent: No-one I know, although there is a cool tshirt
This version challenges the underlying premise of the above two arguments: that we need to slap labels on any attempt to be merry and generous. This assertion is clearly silly, and yet so many people take it as a given (admittedly mostly at the instigation of that scourge of wallets, the greeting card industry). Why not just have fun?
Go visit your relatives not in celebration of one particular baby out of the billions who have been born in December, but because you love them and want them to be happy during this frankly rather gloomy time of year. Go sledding not from any sense of obligation, but because sliding down snow is great fun and probably won't be possible once global warming really kicks in. Buy people as many presents as your heart desires and your bank account can cover, but don't forget them the other 364.242375 days of the year. Stick up a Christmas tree not because you need to compete with the Joneses next door and their indoor redwood, but because it's hilarious to watch your cat trying to mug the fairy on top.
In short: treat December 25th not as some bizarrely different chunk of time, but as a linchpin in your plans to fill the entire year with as much happiness as possible. And as a chance to get completely plastered, of course.