7 colour printing? Anyone remember Hexachrome? That was CMYK+Orange+Green usually.Joking aside, the HP Indigo is a 7 colour digital press which I have seen amazing results from. They were running CMYK+ Orange+Violet. Good for more accurate colour matching of the Pantone gamut which CMYK can't do very well. It's supposed to be able to run spot colours as well. I used to have a 6 colour desktop inkjet which was great for photos (CMYK+lightC+lightM).