I hadn't realised that the post office in Finland issues postcards of their stamps, rather like the UK PHQ cards. If it's something regular, I feel a new collecting theme coming on.
Of course, given the lack of a red nose, it can't be Rudolph. I think it may be Dasher during a quiet moment.
I do have a number of other Christmas stamps, of course:
Also from Finland
And from Poland:
This is a post for Sunday Stamps, now hosted by Violet Sky at "See it on a Postcard!"