Homebrew PCBs

I think this is also a great question - how to apply solder mask at home.

For all you chemical gurus on this list, couldn't you mix up a solution of
wet solder mask material, put it in a 'drafting pen' and then use an HP
plotter to 'draw' the solder mask on the board? You would just have to
create a file that draws everywhere you want the mask to be. That isn't
hard. The hard part (to me) is to find the right stuff to put in the pen. I
would assume that you'd then have to bake the board in an oven or something
to get the liquid solder mask to dry.

Can the same thing be done for do-it-yourself silk screen? I would guess so.
We'd just need the right 'ink' to put in the pen and then draw on the silk
screen layer. What type of ink could one use?

*Brian