Unfortunately for these die-hards, new trackballs don't come around all that often, so it was worth taking a look at Kensington's Orbit Trackball with Scroll ring.
*There are also the touchpad users, but that's a whole separate topic.
At a Glance
The Good: Comfortable, affordable
The Bad: Not wireless, "optional" wrist rest not really optional
Rolling, Rolling, Rolling
Despite its large footprint (which is extended even more so with the wrist rest), it’s helpful to know that you don’t need a large mousing area. This is a plus if you have a smaller slide-out keyboard tray on your desk -- once you make space for it, there’s no need to move it.
The actual trackball is a glossy, attractive blue sphere located directly in the upper center of device. The scroll wheel surrounds it, and large left- and right-click buttons flank the scroll wheel. I found that my left thumb naturally gravitated toward the left-click button, while my pointer and middle finger operated the actual trackball. This left my ring finger to alternate between using the scroll wheel and the right-click button.
Scrolling, Scrolling, Scrolling
For someone who frequently experiences shooting pains in my wrist from lengthy periods of mousing, I found the Orbit with Scroll Wheel to be extremely comfortable. Yes, it took some getting used to, but the wrist rest (also rubberized) fit neatly where it was supposed to, and I imagine experienced trackball users would take to it quickly.
Cut the Cord
The Orbit with Scroll Wheel is one of Kensington's most affordable trackballs. However, you do give up certain things, such as the media control features found in the company's Slimblade trackball. But with the features you do get -- the scroll wheel and the tracking comfort -- it's not a bad deal.