JB Hifi is currently selling Logitech MX Ergo mouse for $90.30 - that's $38.70 cheaper than normal price.
Logitech's most advanced trackball for trackball enthusiasts and consumers searching for alternatives to mice and touchpads. Delivers 20% less muscular strain compared to a regular mouse. MX ERGO features a unique adjustable hinge for personalized comfort and the latest tracking, scrolling and power management technology. Logitech FLOW™ enables effortless cross computer control.