You described it perfectly. I've noticed the "power" as well.
Teachers never call on me in class, even though I'm obviously not paying attention, I've even been sitting in the front of the room doing work for another class while the teacher was trying to teach, and they don't notice, while with anyone else, they'll get yelled at instantly.
I never fall under suspicion of doing anything, it isn't even thought of by anyone. I walk in late to class, and no one notices. I've bought $3 in merchandise at the store, and am wearing a baggy sweatshirt with odd shapes showing in the pocket, and I don't even get a second glance from the security guy at the door. I'm setting off a huge quantity of fireworks in my front yard, the police officer just keeps driving by, and the same guy the next day gives my neighbor a ticket for a some tiny firecrackers.
No one ever thinks I'm listening or care about whatever it is they're discussing, because I'm quiet and generally keep to myself. I'm ALWAYS listening, and as you've said, I find out a ton of useful information from doing so.
I also kind of like how surprised people are when I do have stuff to say and the like. (Note: With friends or people I know well, this is different obviously).
I can definitely relate. It's kind of nice once you realise what it is that makes people do that (which is, mostly, looking like it is a perfectly normal and natural thing for you to be ignored...as if that is the natural order of things and neither you nor anyone else should be bothered by it because it simply is).
I particularly have had the "late to class" thing. I can walk in late, state that I'm late, explain why I'm late and the teacher will do nothing more than nod and maybe smile and then fail to mark me tardy. It's very weird.
"I took the one less traveled by,
And that has made all the difference."
As even introverts comprise the external social and physical reality, we must sweep you with our lidless Sauron-like radar. For true invisibility, office doors work well, though. Any doors really.
Yeah, see I'm kinda in school so I don't have that luxury. I wish I did though to a certain extent, because honestly I really don't have that much energy or necessarily care to put enough of a facade to pretend like I do. Doors sound excellent though, maybe if I had my own room...
My cold, snide, intellectual life is just a veneer, behind which lies the plywood of loneliness.
Why would I care if somebody wanted to be invisible? I have my own life to live and my own work to do. Carry on, I say. I don't see how that would be frustrating to me unless you were hiding out just so you could slack off, but it sounds like in your career, your best work is done solo. I have a lot of respect for people that I consider intelligent.
"When a resolute young fellow steps up the great bully, the world, and takes him boldly by the beard, he is often surprised to find that it comes off in his hand, and that it was only tied on to scare away the timid adventurers." - Ralph Waldo Emerson