I've been thinking about making my own with load cells, but I guess looking up those patents and seeing how IBM/Lenovo did it is a good idea before I start. It

I've been thinking about making my own with load cells, but I guess looking up those patents and seeing how IBM/Lenovo did it is a good idea before I start. It really doesn't seem hard though. It seems to me the trickiest part is getting the acceleration curves set correctly so that it feels nice to use. But that should be a matter of software/configuration, not hardware. High resolution readout from the load-cells seems essential, so that you can have precise readout of very low forces, giving the trackpoint a light and airy feeling without compromising precision.