Better: labeling to state that the device is explicitly equipped against unwarranted surveillance. The message of avoiding surveillance might be more useful than the act of frustrating it.
Oh, nice! I was thinking of something that would blend into the frame of the laptop, making itself unnoticable (unlike a post-it note - which would look rather ugly). But having that message would probably appeal even more because at that point it becomes a form of protest rather than just a quiet security measure.
Better: labeling to state that the device is explicitly equipped against unwarranted surveillance. The message of avoiding surveillance might be more useful than the act of frustrating it.