Hi there i've had a powerball for a couple of years now, but i recently upgraded to a new one and never knew how much better they are new.
I created this workout tool to help get my strength up, i've been using it for a 2 weeks now and it clearly displays how much i've improved, from a high speed of 10500 to 13772.
Extract the file to My Documents
and read the Read Me.txt
you'll need microsoft excel (i used 2007 but i think i should work with earlier versions and definitely with later versions).
i'm right handed so the program works better for rightys, however you can change every right to left and left to right if you want, the Read Me explains how to edit the file.