I once borrowed someone's car, while I was pulling it out of the garage I heard a crash just to my left. I had forgotten to close the driver door and nearly pulled it clean off.
The most expensive thing I broke was my ceiling fan, I was thinking " I wonder what would happen if I threw 100 of those plastic lays into the ceiling fan? " I did that and a blade fell off.
A sink. My mom was going to install one. I was playing with my elderly beagle. She ran, and I ran after her, and we bumped into the sink. It fell over. Thank God not on my beagle. She lived another 2-3 years.