Often called "Fireplace Props", sometimes they get a new lease of flying life.
Back in 1994, my Taylorcraft was involved in a collision that rendered our metal McCauley propeller unusable
. The pilot on that day, John, hung the now defunct and damaged prop in his workshop as a "memento" of that day.
Some years later in about 2006, we fitted a C-85 engine instead of the old A-65...and looking up at the prop in John's workshop, I said to him: I reckon that will fit the C-85.
It did (after being cropped, re-pitched and repaired and re-certified at a third of the cost of a new one). It is now back on the same Taylorcraft to this day.