Collapse: How Societies Choose to Fail or Succeed, by Jared Diamond, has dropped to $1.99 at Kindle and Kobo US. Diamond is perhaps better known for his Pulitizer prize winning Guns, Germs and Steel, although Collapse is so topical, both for today’s world and some of the countries in it, that by now it may be the better known. Both of them (and a couple of his other books that I’ve read) are awesome. I live near UCLA, where Diamond is a prof, and was lucky enough to hear him give a lecture in person one time – he was very engaging, as you would expect.