Have only fished in small lakes in the middle of Alberta, Canada so I have limited experience.
Fishing line with a nice hook still on it.
Caught the dog (was trying to fetch the hook).
Caught the cat (was loading rod into car and it grabbed the bare leader)
Caught my Dad, Uncle, Grandpa (typical for a 6yr child)
Caught my line in the motor prop
When I was 7 a 40" Northern pike almost dragged me off of the boat, it was literally dragging me - my Mom came to my rescue.
My dad thought he caught a log, but it turned out to be a 5' pike which was missing one eye - they dragged into the boat with a landing net and one hell of a fight.
My teacher was fishing for trout in a stream and accidentally snagged a beaver that was swimming submerged. 40lb beaver and 12lb line don't mix so well.