British spies at one point hatched a plan to feminize Hitler a little by doping up his food with estrogen. Professor Brian Ford of Cardiff University discovered that, and other ingenious plans in old unclassified documents, and outlines them in Secret Weapons: Technology, Science And The Race To Win World War II.
Would it have worked? He had tasters so poison was a no-go but estrogen has no taste. If they were able to slip him estrogen, there is no record of it. But Stephen Adams, Medical Correspondent at the Telegraph, talks with Ford about that and also discusses other neat secret plans, like trying to drop glue on soldiers to make them stick to the ground and dropping poisonous snakes on them too.