This discussion on hackaday.io, itself a most interesting web resource for a universe of ideas, questions the lack of hardware choices for persons keen on enjoying the freedom to hack one’s own printer, either at work or home.
It may seem hard to believe, but early printers for computers actually came with code that users could load up on their (room sized) devices, and tweak to achieve some needed variation, or just for the heck of it.
One day, at MIT, a new printer was delivered, and it came with locked code. One of the researchers using the department computer was outraged, and tried to persuade the manufacturer to make the code available for modification.
This did not happen. Out of that small loss, a great victory emerged, the world of Free Software, and the Free Software movement. The researcher, Richard Stallman, has become the lead figure in a pantheon of great people who have been at the forefront of a demand that technology be at the service of people, and not the other way around, which is the foundation of the industrial society.
That husbanding of knowledge is also the underlying philosophy of fiercely competing political systems, despite claims to the contrary.
To return to the first linked page, do read the exchanges between James Newton, Starhawk and Peter Walsh, in particular, though the whole thread makes for good reading.
It seems that it is actually quite possible to purchase some of the sub assemblies that a modern printer comprises, and put them together with hacked code, and some good assembly skills (given appropriate tools in the workshop, of course). But nobody seems to be actually doing it, or to have done it.
There are some interesting ideas in the thread — for instance, instead of using ink/toner in a b/w printer (like a laser printer), the paper itself can be scorched black, or blackish.
There could be other ideas the makers of inkjet printers aren’t doing.
Even inkjets themselves (the printing heads) don’t need to be mounted only on an x-y assembly. They can be mounted on handles, and used to place ink on large or random sheets of paper, to create artworks on a massive scale. This has been done in the past, and publishing a project to do it again could be a very useful service to artists.
And there are probably a lot of ideas that haven’t been tried, in a world conditioned to think that x-y printers should print on A4 sheets of paper.