I became interested in gray when I was upgrading the townhouse I bought a few months ago. Everything in the house was shades of beige, including the walls and carpeting. I had Gray Flannel Oak laminate installed throughout to replace all the wall-to-wall carpeting. I left the tiled areas (bathrooms, kitchen, front entryway) intact. Then I got a Sherwin Williams color catalog and went through all the grays. I wanted a true gray, not mixed with brown, yellow, blue or green. I placed about 20-30 shades of gray next to each other and weeded out any that had a 'tint' to them and came down to the one true gray color I wanted. It's Sherwin Williams "Morning Fog" 6255. It's a very rich medium gray, not too dark, not too light. I contrasted my kitchen area with Sherwin Williams "Fusion" 6919, a kind of electric lime green. The Morning Fog and Fusion look very contemporary and hip, very Seattle, New York. I've eradicated all beige in the house. I chose various other colors for the bedrooms and baths, but the majority of the house (entire downstairs, stairway, entryway, upstairs hallway) is done in the Morning Fog. It looks fantastic and very contemporary!
According to Popular Science..com, the average human being can really only see 30 shades of gray, but we can see 10 million unique colors. I thought this was interesting. They did this study in relation to research about E ink (you know, the ink that is seen on Kindles)