Wilhelm Mohnke: "Bonkers" - Due to the difficulty English-speaking viewers sometimes have in pronouncing his name, many fansubs have taken to calling him "General Bonkers", because "Mohnke" sounds somewhat close to this. The in-universe fan-joke in Hitler Rants is that Hitler is the kind of annoying boss who invents demeaning pet names for his subordinates, but Mohnke is too afraid of Hitler to correct him. Other joke fansubs straight-up say that "Bonkers" is his actual name.
Hans Krebs is known as "The Map Pointer" due to the iconic Hitler ranting scene.
Wilhelm Burgdorf is "Boozing Burgdorf", and less commonly "Fast-Talkin' Boozin' Burgdorf"
Bruno Ganz (Adolf Hitler) was offered the role of Oskar Schindler. He refused and the role went to Liam Neeson.
Even more hilarious is that both Bruno Ganz and Alexandra Maria Lara would later play Holocaust survivors in The Reader.
What Could Have Been: Oliver Hirschbeigel almost didn't direct the film, trying to leave the project to jump to another project that had just lost its original director. However, his contract stated that he couldn't leave the project and had to direct the film. The film that he tried to jump to? Blade: Trinity.