As is my habit, I went out to my garage this morning, water bottle hand, to hop on my ride du jour - in this case one of my green Super Courses.

Tragically, I noted that once again, someone or something had been messing with it again and the rear tire was flatter than a pancake.

Given the number of bikes in my hoard, it had been a month or so since I last straddled it, but at that time both tires were aired up fully and exhibiting no issues whatsoever.

Now, this is NOT the first time this has happened, virtually at random. No bike in my stable is immune.
We are not talking pinch flats here - I KNOW how to mount tires, and when (and if) I can detect the source of the leaks, they're miniscule.

-So who is sneaking in and flatting my tires with their nefarious little pins?
If I wasn't one already, it would make me a conspiracy-theory-believer!
...or then again, maybe it's aliens.

Has anything like this ever happened to you?
-Or are they only out to get me?