WWII German Submarine U-1206 Sunk by Its Own Toilet: https://www.youtube.com/watch?v=-b5AwYJcuis (about 4:23 minutes long) – you can’t make this up.
To be fair to the toilet, the toilet was only indirectly responsible for the sinking as it forced the U-boat to surface where it was caught by Allied aircraft forcing the skipper to scuttle the U-boat.
Wikipedia article: https://en.wikipedia.org/wiki/German_submarine_U-1206.
Good to see they located the U-boat as the skipper’s original location for the wreck was off. It was only about 3.7 miles off.