Hi guys, I came across this item on Amazon today, and wondered if anybody was using one? http://www.amazon.co.uk/Nsd-Powerba...sr_1_1?ie=UTF8&s=sports&qid=1254675645&sr=8-1 Supposedly great for musicians to strengthen hands & arms, good for RSI etc. As I am not still young as I was, with playing bass and trumpet I sometimes get aches in my knuckles, and with a recent purchase of an Eminence I could probably do with strengthening my hands for pressing the strings. Does anybody have good/bad news to tell about this thing, seems they were developed by NASA to help astronauts in zero gravity maintain strength. Thanks for any feedback.