It's not a note but I can remember some Pfennig coins from the times of Deutsche Mark. There were some 1, 2 and 5 Pfennig around, which were produced in 1948 and 1949. They looked the same like the newer ones but on the back was written "Bank Deutscher Länder" instead of "Bundesrepublik Deutschland". They were quite rare in the last years of DM and most people didn't realized they have them because they looked same like the newer ones except for this writing. I think somewhere I still have some of those.