My favourite moment was when I tried to figure a specific software issue out that had to do with obscure hardware and after hours I found one forum post detailing the solution with zero replies. And it turns out I wrote it myself, years prior and had forgotten about it.

I googled a command line string to do XYZ thing once, and found my own blog post.

I really do write that stuff for myself, turns out.

I had a similar experience involving something dealing with RSA encryption on iOS.

Or even worse, you ask an "xyz" question in the "xyz" StackExchange, then immediately get flagged as off-topic

"Nevermind I figured it out"