Whenever I leave my computer for the bathroom or anything inside the living space, I press
WinKey + L to enter the "Lock Screen" mode. (If I go outside, I turn it off completely.)
Let's say that somebody is in my house. I lock my PC in the manner just described and go to the bathroom. They immediately pick out a little USB device hidden in their pocket and stick it into a USB slot on my computer. It does "something evil", they unplug it and go back to looking innocent.
I come back, unlock it and continue working, but now I have some spyware on it.
Is this reality? Surely Windows must ignore anything inserted while in the Lock Screen mode? Please tell me it does. If not, and it actually runs stuff behind the scenes even then, I've just become even more paranoid.