Have you tried one of these? What do you think of them? If anything they look like a fun toy! But are they of any real benefit? http://www.powerballs.com/
I bought one of these to help regain movement after I broke my wrist really badly . It was brilliant and really fun to use. My nephew ( 15 years old)had one for Christmas from me as he liked mine so much. Be warned they are very addictive and can be a huge timewaster.