[Tech1]

These are still (very rarely) found by hikers in the pacific northwest (source: i'm a bomb tech).

Other relevant / weird WWII reading: https://en.wikipedia.org/wiki/Bat_bomb (US program) https://en.wikipedia.org/wiki/Anti-tank_dog (Russian program)

[YeGoblynQueenne]

And let's not forget more recent efforts:

https://en.wikipedia.org/wiki/Military_dolphin

[tdeck]

Another crazy one was pigeon-controlled missiles:

https://en.wikipedia.org/wiki/Project_Pigeon