Ability to reverse the highlighting of the grid overlay

I don't know if it is useful to anyone else, but I prefer to have the gutters highlighted, leaving the main content area "transparent". I created a patch (and the necessary images) to accomplish this. It would be cool to see this implemented, but understand if not enough people like that layout.

Currently the images are supposed to go in a /reverse subdirectory under each of the 3 grid settings directories. So the directory structure would look like this:
omega
- alpha
-- css
--- grid
---- alpha_default
----- narrow
------ reverse (3 grid overlay files go in here)
----- normal
------ reverse (3 grid overlay files go in here)
----- wide
------ reverse (3 grid overlay files go in here)