I'm apparently on the always-harass list. After getting searched before going onto airplanes so many times, I've learned a bit about the procedures involved. When flying on Alaska/Horizon, if you're marked to be searched your boarding pass says SSSS in the lower-right corner. Conveniently, you get your boarding pass before going through security. This is presumably so that any would-be hijacker can see that they're going to be searched thoroughly and drop off all their weapons before trying to get on the plane, to avoid all that trouble that catching and detaining them would cause.
My last flight I happened to be sitting next to a pilot deadheading back. He confirmed that security searches pilots too. Whoever designed current airport security procedures might have a reasonable excuse for this ineptitude though. For example, they might still be in kindergarten.
The SSSS mark has a 2d bar code above it. I wonder if anyone has ever collected a bunch of those and decoded them.