Discussed here, 6 months ago: http://news.ycombinator.com/item?id=1183986 (similar 'Betascript' in Amazon UK)

(The numbers I collected haven't gone down - they're at 36k/23k today, and the "books" seem available. Actually, the listed prices now seem higher than I remember back then, e.g. currently 32 GBP for 124 pages worth of Wikipedia articles.)

P.S. also, last April: http://news.slashdot.org/story/10/04/03/2112203/Print-On-Dem...