I tried using this thumb-joystick with the 2 potentiometers built into it. I'm sure everyone by now has probably seen them, they look like they're excess from standard video games:
I'm going to spare my venting about how many hours I spent checking over my work, and summarize my issues:
The stick is only sensitive within a 45-60 degree range at center. The stick will physically move beyond that point to it's top limit - however, not provide any additional electrical resolution back, and reach the maximum 1023 analog value, about 1/2 way inbetween center and extreme exterior edge. The outer region is useless and all the precision is used up in a tiny 3/8" area - which isn't very useful for my design and test purposes, to guide a camera pan/tilt or laser-pointer so my cats can chase.
I am going to assume these were designed intentionally this way, since boys are rough on toys and a person had to design something that was useful for video gaming purposes.
Outside of this, I found a few other interesting joysticks on ebay, the obviously cost a little more that work excellent:
I actually bought one and it works great, I will buy another one - they have 2 styles, one with spring return and one without.
So what I can't seem to find are the leftover spare parts from R/C hobby joysticks, like the single lever type and such. I was also looking for something like a slider, linear potentiometer - that had a middle-spring return. It would be nice to have a bunch of different stick options in my case to pick from different types of sticks to use to design an interface. Can anyone show me / link to some other options ?