I've learned quickly from the more tedious class-assigned readings that page numbers cause serious, unnecessary grief ("oh what crap, 20 more pages..."). I propose heat-sensitive page numbers -- they're a blacked out box to prevent you taking a peek. Hold your thumb over the box for a bit and it'll reveal itself. Of course, if you want to find a page, you'll have to stick the book in the microwave...
Other variations on this same idea could use electromagnetism (using Xerox's reusable paper technology), or using some kind of intricate shutter system (a switch on the spine of the book -- "on" or "off"?).
Or just make unnumbered editions of books.
I'm sorry if this is too vague -- it's been a while.
Back to reading.-- oatcake, Nov 13 2003 Xerox's reusable paper http://www2.parc.co...l/projects/gyricon/ [oatcake, Oct 04 2004, last modified Oct 21 2004] I dunno. I rely on page numbers to warn me that the author, having spent breathless 450 pages backing his/her protagonists into a tight corner, is going to resort to some tacky deus-ex-machina to pull them out of it in the last 5.-- DrCurry, Nov 13 2003 I rely on the thickness of the book to know how much is left, which makes this idea somewhat redundant.-- hippo, Nov 13 2003 I do like the idea of hidden passages in the book.-- normzone, Nov 13 2003 I also like the idea of hidden passages in the book.-- phundug, Nov 14 2003 Interesting possibility of reading between the lines; have one set of printing on the page that appears at a temperature that causes another set to disappear.-- half, Nov 14 2003 It's interesting that, with the rise of e-book readers, it is getting harder and harder to count pages. In fact, if a school textbook is e-bookified, how do you even refer to particular pages? Are the page numberings "suggested" by the publisher?-- phundug, May 12 2011 You could print the different information in differently coloured ink, and wear coloured spectacles to view the desired information.-- pocmloc, May 12 2011 random, halfbakery