Here is a "very" good grey color from Essie.
Chinchilly is a part of Fall 2009 collection and it has been one of my staples ever since.
It is described as "a sleek granite gray" on the essie site, but that kind of simple description wouldn't be fair for this complex & incredibly chic color.
You can see taupe and even some green undertone in this grey color, which makes the color very wearable for almost any skin tone.
True, Chinchilly doesn't top my all time favorite Merino Cool, which is the best looking greyple shade against my skin, but I wouldn't be without Chinchilly since it is such a classic.
It is very office-appropriate but not boring at all.
To be honest, it is even a bit bad-ass looking due to the slightly dirty quality. lol
It looks better if you wear it during the colder months, in my opinion.
If you are looking for a medium toned (not too dark) grey shade that doesn't look harsh on your skin, this is it. :)