I once knew an inmate (I worked for the Dept of Correction) who flushed an entire mattress down the toilet. Probably comes from having too much time on your hands.
How did he cut it up? LOL. A long time ago I worked maintenance in a high school for a few weeks. Several times a week a Skoal can lid got flushed. They were hard to snake because they would simply flip over not allowing the auger to catch them.
In the nursing home the next worse thing was a patient who put paper towels in their sink and left the water running. That would flood at least two rooms for several floor below. One patient was right over the electrical switchboard and did it twice. I went in and cut the water off to the sink. There was a 2000 amp distribution system right below.