5 A Little Ball of Power!!crazynutter2000 | 17/05/2007 | See all crazynutter2000's reviews (9)Top 100 Gadgets Reviewer Top 100 Sport and Outdoor Reviewer This thing really does work! This is too much fun to be a exercise.Warning - Strangely AddictiveWorks Straight out of the box, will take you a few goes to get used to it, but you will know when you have mastered it and will always get it going the first time afterwards.The idea is basically a ball within a ball, you start of by spinning the inner ball using one of the two strings provided, you then move your hand in the same cycle as the inner ball creating a gyrosphere, this will only take a couple of seconds so you then work towards increasing the speed and RPM, therefore increasing the resistence and effectiveness of the excercise.it becomes quiet addictive and you will just pick it up and start working out without even realising it. Personally it has turned into a game of how fast i can get the RPM up too. All the info of the workout is clearly displayed on the LCD display.Works mainly the forearms, but i have found that by simply raising the ball above your head that if you keep a straight arm, turns into a extremely effective Tricep exercise.Only Downside with the Powerball are the strange looks you get wilst using it, to be honest you will look a bit weird when you reach the high RPM's and i seem to keep losing the strings you get with the powerball.Overall, Great Product, Great Exercise, Great Game and totally addictive!