Magic memory trick I pulled on myself today.
Somebody lifted my Debit card and placed a bunch of unauthorized charges on it.
I of course cancelled the card and the bank is sending me a new one.
Today I opened the mail and recieved a new PIN for the yet unrecieved Debit card.
I looked at it for a millisecond or ten and thought “I always change those at the bank right after I get them.” So, I tore off the PIN for future reference and placed the remainder of the mailer in the trash.
About 8 hours later, I took the trash out. I looked into the garbage and I saw the mailer with the missing corner torn out.
Suddenly the thought appeared in my head. “Hmm, I think that PIN is just like my alarm code at work”
I opened my wallet, took out the inversely shaped scrap of paper, and sure enough, the first 3 digits where exactly the same, and in the same sequence. The final one was different, but it was a mixing ups 3’s and 8’s,  Pretty darn impressive for as long as I glanced at it.
That definitely was from a part of my brain I don’t know how to use. I was blown away.