I have a problem that I suspect many others here have had with math and science papers. I have a number of PDFs that have real text (as opposed to images of text) in the file, but the encoding is different. Sometimes this happens with LaTeX documents, sometimes for other reasons that aren't clear to me. Regardless, this robs me of my ability to search or copy: it's not much use to grab " !"# $%#!% #&" ' ($ %) *" !" %) !%+" %) ,- " #&" " from a file. Exporting as an image and OCRing is possible, but the quality degrades so severely that it's not particularly usable. (I don't actually know why the quality is so bad with an export, but it is...) You'd think there would be a way to have Acrobat look at the actual shape of the letters and OCR that... If it helps, I have Acrobat Pro 9 here.