Five Buck Book
Got five dollars lying around? For $5.00 (plus, um, $7.50 shipping), you can snag a copy of George Nelson's 1977 classic How To See: A Guide to Reading our Man Made Environment from Design Within Reach. (While supplies last.)
In addition to being the least expensive item on DWR's website, this 2003 re-release of Nelson's treatise on interpreting the visual vernacular is a good read and genuine bargain: Published by DWR, it includes 50 essays by Nelson and 100 color plates from the designer's own archives, plus new graphic design by Chris Pullman, who ran Nelson's graphics office in the 1970s.