UltraMouse 

UltraMouse is a very cool utility to help you make better use of your mouse by popping up a button menu and othermove-based trigger, you can assign a function to every trigger, the functions includes simulate keystokes, launch a file and more.
mouse driver mouse download 3-button wheel mouse middle button mouseware mouse tool

Cool Mouse 

The right-mouse button in Windows gets a good workout, but that poor old middle button on three-button mice gets ignored. Cool Mouse rectifies that.
cool mouse software tility sharware microsoft middle mouse button