To thrive, Brick and mortar retailers must offer only the biggest sellers. So movie theatres only show the latest runs and Walmart only carries the biggest selling CDs.

But micromarketing and recommendation engines allow the "tail end" of the market (i.e. the non-big-sellers) an opportunity to enjoy access to large markets. Chris Anderson proposes the future of entertainment is in the millions of niche markets at the shallow end of the bitstream.

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