This Orbita Mouse is basically like a Griffin PowerMate in mouse form. It turns, clicks and even right-clicks, but it takes a few minutes/hours of frustration to get used to. And, it's expensive—but it is unique.
$98.50 $70 on Newegg
Too expensive to be worth it.
The Cyber Sport Orbita Mouse is an interesting anomaly in that it looks and behaves totally different from any other mouse on the market now, but actually does exactly the same things as what you've got in front of you. There's the standard right and left click, then you can twist the mouse to scroll up, down, left or right. If you're familiar with the PowerMate, it's that, plus a right click button.
Despite what the site says, it's not an ergonomic mouse—not when compared to an actual ergonomic mouse—but it does scroll satisfyingly when you twist. Its most annoying factor is the first few minutes or hours when you start using it, thanks to the fact that you actually have to calibrate the mouse. The instructions aren't clear enough to get it done right on the first try, so you may have some bad luck before you finally get the thing to work properly.