Just uploaded this desktop wallpaper to n900wallpapers. I'm sure people will find it silly or unnecessary, but from what I've seen and heard the N900 wont come with a "snap-to-grid" option for the desktop icons, so I thought I'd put this together in the hope that it helps someone to better align their desktop icons.
Obviously, this wouuld just be for temporary use whilst placing icons, etc. then you'd switch to your proper desktop image.