I think I'm done with this experiment, for now...

One last photo before I go... This is the "rub-on" etch-resist I used for the really fine-pitched parts of the PCB layout...

This stuff's amazingly easy to work with, you just rub a ball-point pen over the parts you want transferred until they peel off the plastic (very noticeable, as it goes from black to gray). Then use the backing material to rub it in to the copper-clad a little more thoroughly.

You can see the rows I used a lot of; the .1in pads with a trace inbetween. That part would've been difficult with my fat-tipped marker.

I have no idea how old this stuff is, it's barely sticking to the backing anymore, and has probably collected some dust/dirt over the years, still seems to have worked nearly perfectly!