I have always enjoyed the holidays with my family, although we never celebrated the religious aspect of them. My parents are nonbelievers who did not want to influence us on religion.
We have this tradition for Thanksgiving that brings real meaning for the day. Before we eat, when most families would pray, each of us would go around the table and acknowledge the things we are thankful for. Not once did any of us see the need to thank a god. As a child I would say something to the effect of " I am thankful to my parents for providing me with all these cool toys and a roof over my head." Each one of us would speak, it took a while.
Our Christmas was very secular as well, my mother would put an angel on top of the tree, but it was symbolism to us. I can't remember a time when I thought Santa was real, I had always been told he was fiction, a neat story. This did not take the fun out of it though, we played boardgames, went sledding and just sat around hot cocoa and talked. We did have another unique Christmas tradition; to be fair all the presents were from 'Santa'. It took away the material aspect of the day, not all of us had as much money to spend on each other.
Now, however, I am thousands of miles away from home and across an ocean. I realize I don't have the same community that a church offers but I do have my fellow servicemembers who are also separated from their families and I have other nonbelievers who understand what it's like to be far from home. The local chapter Of Military Atheists and Freethinkers hosted a thanksgiving dinner that felt almost as good as home and my unit had a dinner, too. During the Thanksgiving I take time to appreciate those who have helped me and those who made the world a better place.
Christmas is about giving back to those people, I donate my money and time to good causes. It's not about gift getting but gift giving, in my version of an atheist Christmas. I am glad to get gifts, yes, but I love that warm fuzzy feeling I get from giving them more!