I've got you beat. How about the hitch pin? I took it in to measure it's length and diameter (I was making something that could be locked with a hitch lock.) then promptly left the pin at work. My only pin.
So that weekend I'm hitching up and yep, no pin. I had the hitch, I had everything. No pin, and it was my only pin at the time.
It being locked up I burned an hour running across town to Walmart and back, plus bought a locking pin.
Now-2014 Sierra 346RETS 5er BUB
Then-2002 Keystone Springdale 286RLDS TT
Nights camped in 2014-28, 2015-127, 2016-10