Ready Made Magazine
"ReadyMade is a quarterly print magazine for people who like to make stuff, who see the flicker of invention in everyday objects..." Full of great ideas for making something useful and unusual out of found objects. It will make you want to head for the ReStore.

Visual Thesaurus
Goveia & Hatmaker
This is a great book for visual people... it works just like a regular thesaurus, only instead of words, it offers images. Good for sparking ideas and finding a new perspective.

The Grammar of Ornament
Owen Jones
First published in 1856, my copy is an updated smaller sized version. With over 2,350 classic patterns derived from architechture around the globe it's all about the use of shapes. Great eye candy.