Illuminated manuscripts are a terrific source of inspiration, particularly for the artist or designer. Unfortunately that aspect of this storehouse of treasure is frequently overlooked in favor of their historical and theological importance.
Creativepro, a resource primarily for graphic designers, has just published an article by Ilene Striver which gives a great overview of the art and design of these manuscripts as well as some nice, lard, clear, images.
The Journal for Catholic Culture & Arts 