The first use of the thin (at about 3MM) large format tiles that the librarians of Library Resources noted, was for use in elevator cabs... particulary for cab renovations, where weight limitations were fixed, and quite often low. Since then, there has been significant growth in both the aesthetic quality and performance characteristics. The "stone look" tiles are finally of a quality that will withstand some visual scrutiny; and the tiles are now coming in thicknesses up to 6MM, improving their performance as a flooring product. The true 4x8 foot panels are probably still going to be limited to the wall for now, but 3x3 foot tile (in the slightly thicker versions) is already making it onto the floor.
Though there are a now a wide range of entries into this market, if you are interested in any of the options mentioned in the first section, links to the reps are as follow:
Stonepeak - Amy Smeigh