The two most popular books on Amazon.com right now are:
Of the two, I prefer the Ladigin as it is more accessible to beginners, friendlier in format and … weighs only 8oz. (It’s published by Falcon, a company we often criticize on this site. Good job with this book.)
Lighten Up!: A Complete Handbook for Light and Ultralight Backpacking (Falcon Guide)
In Australia I was surprised to see the vast majority of hikers with heavy, traditional (out-of-date) gear. The lightweight movement clearly has not reached Down Under.
Experienced ultralight hikers will find more of interest on-line. But the inexpensive Ladigin book would be an ideal gift for any hiker you know who could easily reduce the size of their base pack weight.
besthike.com 