As a matter of sheer restless curiosity (and possible future exploration), I'm wondering: Is RA-4 the only game in town now when it comes to (analog) color printing? And for that matter, what color printing technologies have come and gone over the past fifty or so years?
Ilfochrome/cibachrome is gone. I know all about dye transfer and that Kodak stopped supporting it in 1994. Too bad -- I had the opportunity to see an exhibition of Mark Cohen's color work a few years back, and the dye transfer prints were beautiful. I believe it's still practiced today by some hardcore enthusiasts who have found workarounds, but that it's difficult and not quite the same.
Some further reading introduced me to the intriguing, though short-lived, Kodak Ektaflex process of the early 80's. Between the developer, which I understand was problematic, and the Polaroid patent suit, it sounds like it was doomed from inception.
What else is/was there?