Daniel Gross, writing in the New York Times today with a very Long Tail-ish celebration (reg req'd) of big markets in small sums, mentions a book I've just started reading. Like the Long Tail, The Fortune at the Bottom of The Pyramid, by CK Prahalad, is about finding ways to effeciently address sub-economic markets. In this case, he's talking about how to sell goods and services to the world's 4 billion poor, for mutual benefit.
Don't be put off by the do-gooder tone and dry textbook style; this an important guide to finding ways to offer products at lower overhead and in lower-cost form to profitably reach markets that previously looked hopeless. For instance, take this table, which when you substitute "niche consumers" for "the poor" and "hits" for "products sold in developed countries", could apply to Short Head thinkers everywhere:
("BOP" is bottom of the pyramid; "MNC" is multinational corporation)
You can get the thrust of the argument in his 2002 article (free reg req'd) by the same name in Strategy+Business. Prahalad is setting up a San Diego-based consultancy to help companies implement his advice, and recently hired my friend and former Economist colleague Azeem Azhar to help him. Welcome to California, Azeem!
More as I get further into the book.