I remember that ravens tale (and yes, it's Grimms/German); as I recall, the heroine had to cut off one of her fingers in order to use it as a key to unlock the prison in which the ravens were being held.


As for Ravens in German / Norse mythology, Odin (ruler of the Norse Aesir gods) had two ravens, which flew around the Earth and reported back to him in the evenings. Their names were (via English translation): "Thought" and "Memory," and Odin was always afraid that they'd fly off one day and never return.