The security used something I would describe as out of an Iron Man film, they were zooming around a translucent 3D view of my backpack. (It was on an LCD display instead of hovering midair, but I was still impressed. But the fact they let me keep the water was even more amazing, hahah.)
I just flew with two laptops in my backpack which I didn't have to take out for the first time (haven't flown in a while), with a custom PCB with a couple of vivaldi antennas sandwiched in between the laptops.
It was a real trip watching them view the three PCBs as a single stack, then automatically separate them out, and rotate them individually in 3D. The scanner threw some kind of warning and the operator asked me what the custom PCB was, so I had to explain to them it was a ground penetrating radar (that didn't go over well; I had to check the bag)
They don't advertise it, I found out by accident, trying to empty my water bottle by drinking when a security person told me to just put it together with the rest of my stuff. I had no idea that was a thing and was pretty confused.