One of the main and most important Allied bombers, the B-17 was sparked interest and greed target of Germans and Japanese during WW2. Inevitably some planes were captured and tested by the enemy. I share with you the link below that has some photos of these planes, some rare, with German and Japanese markings. To see the photos, visit the link below:
http://aviacaoemfloripa.blogspot.com.br/2011/02/fortalezas-voadoras-capturadas.html
Best Regards.