We do the pajama thing too. There's just nothing quite as sweet as excited kids in new jammies on christmas eve/morning.
We also have a traditional breakfast on xmas morning. Its this super-delicious super-easy monkey bread that I make the night before and just pop it in the oven to bake while we do presents and stockings.
We also drive around and see x-mas lights which is always fun since we live near a lot of wealthy neighborhoods that go "all out" every year.
Oh, and one more thing. We always sprinkle "reindeer food" on our lawn (granola, cheerios, raisins, anything we find in the pantry lol) and hang our "santa key" on the doorknob so Santa can get into our house (we don't have a chimney).
Oh, I'm just getting SOOOOOOOO excited just thinking about it! Christmas is my favorite time of year!!