Nina Simone was an artist that presented herself from the bottom of her soul. In my opinion the following clip is a presentation as opposed to a performance. What we see here are Nina's "feelings" coming to life on stage. The few other clips that I have seen from that time at the Montreux Jazz Festival were equally compelling each in their own right.
I'm not going to fill up with the clips from that show here but if you're interested, go to youtube and enter "NINA SIMONE live at Montreux,1976" in the search box. I promise you won't be dissappointed, unless someone takes these clips off youtube.