This Mondo Nuvinci review was written by Val Kleitz, originally posted to phred.org, and is blogged here with permission. Below are related links and videos.
Since before the turn of the twentieth century, the development of gearing systems for bicycles has inspired a vast amount of technical invention and innovation. The overwhelming variety of drive train styles has been the subject of many articles and several books, and new developments continue to appear. One goal that has obsessed inventors almost from the beginning has been the creation of a continuously variable drive system. There have been many attempts to build such a system, which would allow the rider to change the gear ratio throughout the range without being limited to specific gear increments. Until now, all the imaginative approaches to this mechanical conundrum have been either completely unworkable, or inappropriate for use on bicycles.