Not sure if anyone has draw attaention to this before ...
Older readers may remember the buzz back in the 1980s when hundreds of books and pamphlets were collected together on microfiche. The short story is that many of the books can now be downloaded for free as pdfs.
As Wikipedia describes it "The Appropriate Technology Library consists of 1050 books on 29 subject areas of small scale, do-it-yourself technology. Originally developed by Volunteers in Asia (VIA) it was transferred to Village Earth: The Consortium for Sustainable Village-Based Development in 1993." Wind power, water power, and house-building are some categories ATA forum members may find interesting.
Some may be aware that there are versions floating around on the peer-to-peer network, seen on such torrent sites as http://www.demonoid.me although one cannot condone that method of getting the AT library. Ahem. Well, there is a fully legal way I just came across: the Faith and Sustainable Technologies website. Not everything is there, and the interface from their homepage doesn't seem to work as intended, but the direct link to the hyperlinked pdf download index is:
http://www.fastonline.org/CD3WD_40/CD3WD/INDEX.HTM
Back when I was a nipper the AT Library all seemed like Aladdin's cave. These days so much of it seems faded, a distant echo from the Woodstock age. Still, some of it is has not dated, such as some of the workshop books and a wee few of the alternative energy books.