The guys over at Hesperian Foundation have made two popular medical books available on .pdf to download for free or you can order the hard copies as well.
via Free Downloadable Medical Guides | The Survival Spot Blog.

James M. found a free 36 hour video permaculture course available online, from the good folks at the LATOC Forums.
via Odds ‘n Sods: – SurvivalBlog.com.

While searching for ways to effectively gauge the accuracy of Mosin-Nagant M91/30 rifle, I came across this file download that had some very good formulas that are simple and easy to use. You can calculate the effects of elevation, wind, and temperature etc. with these simple formulas.
via Stealth Survival: Free Download – Mathematics for Precision [...]