Here you get three techs for the price of one. Alder Hampel from 10th Planet Jiu Jitsu Hollywood goes over three techniques in the morning class at Legends Gym.
The first technique is a little nuance to the Electric Chair when your opponent bases out with his hand to prevent the sweep. I won't give away the detail but it is as effective as it is funny. You have to check it out.
The second technique is a sweep from the Dog Fight that he calls the Red Baron.
The last technique that Alder goes over is the Darce from Side Control and a few of the details that he uses to make it work.