Wanna make a scope? Or better still, grind a mirror yourself. Or, you have some good tips in making a really useful accessory? This is the place to show what your hands can do...
was checking around, most projector(vga,svga,xga) usually have lens from 60-80mm. dunno if those can be used to make a refractor. electonic-focusing of the lens holder seems fun, and most lens seems to be built very well, sharp and distortion free.
I believe it is not ground to the required precision. i.e. you will not get sharp images of pin points. Also, the optics would not be coated to remove chromatic aberrations. Many years ago, I used spectacle lens as objective. I experienced horrible CA.