I ride with a prosthesis, so it's not a one-foot issue. To be precise, I sort of have 1.5 knees -- my operation (a Van Ness Rotationplasty) was somewhat unorthodox, but it works very well: http://www.wmt.com/expandableimplant...amputation.asp. It gives me much more mobility (pretty much that of a below-knee amputation) than the other option, which was to cut the leg off well above the knee. Unfortunately, not many people know it's an option, and sacrifice a lot of mobility as a result.

I don't have a particuarly strong death wish, so I'll be keeping the front brake.