My best recollection of Christmas was actually believing and "knowing" that Santa was real. I remember waking up at the crack of dawn before my parents even woke up out of sheer excitement.
I would rush to the living room, and see the pile of presents under the tree, the empty plate and glass where the milk and cookies were, and a note from Santa.
Immediately after that, I would run to wake up my younger sister in an excited state of euphoria, announcing that Santa had come!!!
After she had her look of amazement at all of the Christmasy glory, we would both run into our parents room to wake them up.
6:00 AM Christmas morning, our mom and dad were awoken to the sound of children whispering "Santa came!!! Wake up!!! Wake up!!!"
Those were amazing times. Now that I have my own daughter of 4, there hasn't been a time yet that she woke up before me. As a parent I still get to enjoy the warm feeling of waking up a loved one to announce that Santa had come! At least for now.
I look forward to the day where she is waking me up with excitement about Santa.