Are you my mom? Are you going to call me when that post-it note disappears and ask me if, for some reason, I know what your password is?

You mean you don't write it on a piece of paper then place it in a room that is barricaded from the inside, but still accessible by a securius route through the building filled with environmental puzzles and enemies? The barricade should also be convenient to move from inside the room for fast return to your computer.