Jouko Ahola, who plays the strongman, is an actual strongman and actually lifted the weights as seen in the film.
The actress Anna Gourari who plays the character Marta Faria is an actual world class pianist and plays all the pieces in the movie with out having to fake it at playing the piano.
The voice of the heckler in the audience heard right before Zishe dead lifts 900 pounds, belongs to Werner Herzog.
An elderly woman who lived in one of the houses near where the marketplace scenes were shot, once stepped out into it with a shopping bag and, even though director Werner Herzog told her it was just a movie set, insisted on shopping and interrupted the shoot for 15 minutes.
After two minutes of the hypnosis scene, the cinematographer started to weave and his head sunk back. Herzog grabbed him and put him softly back to the camera where he continued. Not only that, but Roth was actually able to hypnotize the young woman as well, again Herzog stating that one "cannot act waking up from hypnosis" like we see in the film.