Step 5: Finished, Future Improvements.
All done, try it out, I find it particually useful when navigating in a 3d enviroment such as CAD programs or Google Earth.
It's also pretty good for programming, scrolling through long files quickly and accuratly, or just giving it a spin to get to the top/bottom of the file.
A shaped case
Though it's not as uncomfortable as it looks, curved edges would improve it.
If I encounter a program that requires a mouse click and scoll for a frequantly used function, I may wire one of the buttons to the side of the case
A more complex improvement would be to have a button click when the wheel is pressed down.
The reason for the big case is the size of the circuit board, if I did this again I'd choose a mouse with a smaller board, or chop the board up and solder directly to the copper traces by the chip.
It'd be possible to use an optical rather than a rotary encoder, it'd be smoother (The rotary encoder has clicks, or notches) and give much less friction, so would spin for longer.
The downside would be the additional complexity oh the build. (And trying to attatch that perferoated disc to the wheel shaft, could be awkward..)
Any more suggestions for improvements?