Okay, so this is a lead up to an instructable that I will be posting shortly; this is the testing I did to lay the groundwork.
I made the assumption that since a laser toner printer was simply selectively melting powder electrostatically deposited on the work piece - the paper - that all I had to do to translate this process to metal to overcome the current transference of toner to work piece! So, to that end I am going to take the powder coating gun from earlier and load it up with toner ink refill (Brother brand, though I'm not sure if this whole process will be very sensitive to the specific mesh of the toner) and I'm going to use the powder coating gun to give the metal an even coat of acid resist that is easy to remove.
The final goal of this is to have a new and less paper dependent method to use for etching homebrew PCBs.
First, I grab just a random scrap of metal lying about and coat it, which turns out great. The touchy part comes when I start trying to get the powder to melt without being turned into a puff of smoke by the laser cutter. This turns out more difficult, but not impossible.
Once I've turned down the laser enough to make a good bit off difference, and less burn off happens, I then start running through etching tests with copper clad board.
At the end of it, it ends up coming down to a rather non intuitive solution; on top of turning the laser's power all the way to minimum, I also have to run the cutter head at slow(est) speeds to avoid 'chop' or stuttering in the traces (which don't contribute to the validity of this method in the slightest). The extra time taken by this 'low and slow' approach isn't very significant vs the benefits gained.
Once all that is settled, it's time to try a real circuit!