Now this is a difficult one to describe, so my best advice is simply to download and try it – you’ll either think this is engenius how could I ever live without that or you’ll think what!? I don’t get it!?
Ok what it does is to optimize wheel scrolling, lets say you have 5 windows open and you have to scroll a lot in these different windows, now the way windows works is that the window you want to scroll need to have focus – so you have to click the window you want to scroll! Well not if you have KatMouse installed, it is quite clever, KatMouse will let you scroll the window under your mouse focus or not, as I said you’ll either think this is immensely clever or not get it.. Try it out and see what you think. (it’s free :-))..