learning english by watching TV

I don't know how effective learning English by watching TV would be, but I remember reading somewhere that the NHK TV network in Japan used to show Sesame Street for adults who were learning English.

When I was taking Spanish in college, one thing I did a lot that I think was helpful was to watch The Simpsons on DVD with the Spanish audio track.

Have you seen the 1979 movie Being There with Peter Sellers and Shirley MacLaine, about a man who learned everything from watching TV?