Remember the days when you just popped in the old Jane Fonda workout tape and worked out? Well there is whole entirely new craze that you just have to see to believe.    The latest workout craze is called 'Prancersize' and simulates the motion of a prancing horse. There really isn't much more we can tell you about it other than you just have to see it to believe it. You can see the workout and how it is performed below and then decide if you're brave enough to follow the trend.