I've had this for years, it's very aromatic and I keep gettig asked what it is but I've forgotten! I cannot find it anywhere in herb references. I've quite a few herbs all of which I know the names of if only because they are commonly used in cookery
One of the artemesias, possibly abronatum
Looks like some kind of lavender to me.
artemisia abrotanum, I'd say.
Artemisia of some sort, but it's leaves look a little wider than the abronatum that I know - there's a list of different artemisias here http://www.perennials.com/plants/artemisia-huntingdon.html which give you pictures if you click on them - perhaps it will help