I studied German at University, and I also spent a year living in Germany as part of my degree. I'm really lucky to have had this opportunity, and the chance to experience life in a different culture. Although I didn't spent Christmas Day itself in Germany, I experienced the build-up, and I loved seeing the similarities and differences in how it is celebrated.
A German (and elsewhere) tradition which I've not really seen celebrated here is the celebration of Nikolaus. It is based upon St Nicholas, who became the inspiration for Father Christmas due to his reputation for the secret giving of gifts. His feast day is the 6th December.
In Germany, Nikolaus is different to Father Christmas, who is known as the Weihnachtsmann. Traditionally, children put a shoe outside their door on the night of 5th December (making sure that they have cleaned them first!). If they have been good, in the middle of the night, Nikolaus will come and fill them with small presents - like chocolate, coins, sweets or small toys.
I want to make this a part of our Christmas tradition, so we did this for the first time today. I'm not sure that Harry really understood what was going on, although he certainly appreciated his chocolate Father Christmas and coins!
More information about the Nikolaus tradition in Germany can be found here.