I wonder if there are any completely automated PCB manufacturing services using DLP technology for the mask, allowing you to scrap the need for masks.
Major PCB producers no longer use masks to make prototype quantities.
I think some places are using ink jet resist printers. Ink jet techniques are gradually working their way into all sorts of production processes, like putting images on ceramic tiles, where a thick layer of the "ink" material needs to be applied. This might mean ink jet techniques spread to more electronics processes. It might be how things like carbon pads and now applied to low volume PCBs.
Some places use projection techniques to expose a photoresist. I believe some of these systems use DLP tchniques, and some use a similar scanning technique to a laser printer.