Scrolling with a Kensington Expert Mouse (Trackball)
EDIT: macOS Sierra broke this functionality. The current version of Karabiner is also different (worse in my opinion). If you are on an older OS, this still works. I’m currently looking for a solution for Sierra and up.
My pointing device of choice is the Kensington Expert Mouse. Despite it's name, this device is a trackball. I decided to adopt a trackball for ergonomics, as your wrist can remain stationary while the trackball is in use. I also considered a trackpad, but I find the trackball is both more confortable to use, and more precise.
Now, there is however one VERY big draw for trackpads: SCROLLING. Scrolling, both vertical and horizontal are very important for getting around your DAW. The magic trackpad is undoubtedly the best scrolling device, no contest. It's ridiculously smooth, and can scroll in very small and precise increments, without stuttering.
The scrolling mechanism on the Kensington Expert Mouse is less than stellar. It's fine here and there, but the lack of precision is something that bothers me even while web browsing. I even took apart the Kensington and removed the magnet, as many others have done, and it's still not cutting it.
After some digging, I discovered that most keyboard customizing software can modify any mouse or cursor movement to become a scroll. Would I ever use this feature for a regular mouse? No. But for a trackball? That's brilliant. So for OS X, all you do is download and install software called Karabiner, and go to town. It's free, and easy to use. So right now I have it set up that when I hold down the command key, my trackball turns into a beautiful, 2D scrolling device.
The software can be downloaded here: