I was once court-martialed for repeatedly pinching my navigator's bum.
Oh, wait, you meant things that actually happen, not things we imagine during a very long patrol...
Okay, well, I was playing a single mission, can't remember which one, bunch of tankers I was supposed to take out coming from somewhere in S America I think and headed for the US or Britain... anyway they looked all alone at first but turned out they had armed escorts and I took a lot of damage before I ordered "DIVE" and things weren't looking good once we submerged so I ordered "BLOW TANKS" and we surfaced and all the other ships were gone except for the little tugboat that graciously accepted our surrender.