I havn't celebrated Christmas for years. I usually offer to work on Christmas day as this means that my colleagues can spend time with their families - plus triple time salary and a day off in lieu for me.
For several years, a group of friends and I would, instead, hold our midwinter celebrations on the winter solstice. We would travel to a particular hilltop in Southern England and have a predawn picnic with mulled wine and mead before setting off some large fireworks as the sun came up and exchanging gifts, we would then go into the nearest town for the largest cooked breakfast that we could find.
Now that i live in Australia. I go diving!