This site isn’t new if you peruse the gallery review sites often enough, but I really love this one. It has clever artwork and the design of the site is created to really focus on that part of it.
Mastering Grids in UI Design: The Backbone of Visual Harmony
A modern guide to UI design grids, learn how to build flexible 12-column and 4-column systems, master margins, gutters, and modules, and apply today’s responsive layout best practices.
Your right, this site has been promoted quite a lot. Just checking the footer of this site explains exactly how may people have done so…. wow….