It's almost sacreligious to have a site focusing on memory without eventually mentioning the name Harry Lorayne. Thanks to his memory course website, there is some great memory demonstration footage available in Flash format.

My favorite of the three videos available on the site would have to be the footage from the Tonight Show. There are several great touches he adds that really helps the performance, such as including the camera operators' names, and commenting on people who switched seats. These small touches really help turn it from a simple recitation of people's names into a performance piece.

Video Format:
Flash