So...when I was younger, I used to have a problem with forgetting 'things'. This wasn't a knowledge problem...I could memorize stuff with the best of them(my strong 'verbatim understanding' skill is one of the things that got me through Nuke School), it was more of a 'Where did I leave this' or a 'Hey, can we go back home...I forgot my wallet?'
More than once, my father hit me with the 'You know, you'd forget head if it wasn't attached to your shoulders!' line.
The apartment we were living in has a fenced/gated patio in the back. When we first moved in there, my wife was talking about wanting to put a lock on the back gate. I threw the brakes on her buying a new lock at the store, and instead we used one of the many 'free' gun locks that any gun owner will accumulate over time.
Now...I am 100% certain, that after placing that lock on the gate, I made eye contact with my wife, and told her 'Okay, let's put the key's to that lock RIGHT HERE so that we can find it really easy when we move in a year.
Which is why I was just at the ACE Hardware buying a new metal blade for my jigsaw. Hopefully it works...it was $20 cheapet than a set of bolt cutters.