Nice irony at the end (spoilers)
Notice how the entire film, Jimmy Stewart's character is peeping in on all his neighbors during their vulnerable moments, like he's watching fish in a fishbowl. Then, at the end when he's being thrown out the window, it's all reversed, and the people in the other apartments are now looking at him while he's going through his catastrophic event.
Well played Mr. Hitchcock, well played indeed!