Last night my wife and I watched "Freaks", the 1932 horror classic by Tod Browning. The film centers on the "freaks" in a circus sideshow, who were portrayed by people with real physical deformities, many of whom were genuine sideshow performers. In the movie, a dwarf, Hans, (portrayed by Harry Earles, a member of the Lollipop Guild in "The Wizard of Oz") falls in love with a conniving trapeze artist who is merely using Hans because he has inherited a large fortune. When the freaks find out, they exact their revenge.
The film was quite creepy, and many of the actors' deformities were disturbing--even more discomfiting to the film's original audiences. The ending was choppy and unsatisfying, and it turns out the film's original ending was cut because it, well, freaked out filmgoers. The DVD's extras include an interesting commentary by a film historian--it's definitely worth checking out.