jim said:

at some point in time in the near future using human beans to make txt files will no longer represent the best technological approach to making PD books available to the public

considering the millions of public-domain books google already offers up, i'd say that that time has already come. most people only want to read the books, and perhaps extract small passages of text every once in a while, and google's production process facilitates those activities... it'd be nicer if all their text was completely cleaned, but one has to appreciate how far they have moved the bar... there's no longer a pressing need for volunteers to do this. of course, many of us enjoy it, so we'll continue doing it...

some Google books have only page images no OCR at all. 

can you give me the u.r.l. of some of those?

where does google do a "slice and dice" -- can you provide a pointer?

in their mobile interface. for example:

http://books.google.com/m#Read?id=rYIhAAAAMAAJ&page_num=123

click on any bit of text to reveal the underlying scan... then click again to toggle back to the digital text copy. -bowerbird ************** An Excellent Credit Score is 750. See Yours in Just 2 Easy Steps! (http://pr.atwola.com/promoclk/100126575x1222585065x1201462786/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072&hmpgID=62&; bcd=JuneExcfooterNO62)