[phkahler]

Your mention of SEM made me think of using something like that to "draw" circuits or some similar method that would be horribly slow for mass production. Imagine if you could build a device that took a week or more to make something that's actually better than commercial offerings. It's a stretch, but hobbyists have options that are not available to big companies.

[polyfractal]

It exists! The technique is called Electron-beam lithography (https://en.wikipedia.org/wiki/Electron-beam_lithography), and it's exactly what you described. It's essentially an electron microscope that is used to etch patterns, instead of doing the whole projection lithography song and dance.

I believe it's used in academic research a fair amount, because it gives very good resolution (sub-10nm) and is very cheap (once you own the equipment). But as you said, it's also very slow :)

There's a contingent of hobbyists that run second-hand electron microscopes in their garage... I'd bet they could do electron-beam litho if they wanted to

[nickpsecurity]

On top of polyrfractal:

http://www.easic.com/