Remember those annoying greeting cards that would play a tinny tune whenever you opened it? That technology hasn't gone anywhere.
Memory chips have gotten smaller, though, so it would be a simple matter of packing a lot more music - or verbiage - into a small chip.
What's the point? Why do that?
Now
let's combine the singing greeting card concept with the coupon book concept, and examine the results.
With conductive inks in the spine of the book, you could make a book of coupons that, according to where the book was opened, would play a vocal message that corresponded to the exposed page. The messages can be anything: company trivia, history, wheedling the customer for his every last dime, etc. You know how the game is played.
The extreme fly end of the coupon page is perfed for easy removal, the rest of the page could be just a book page.
In order to REALLY draw in the customers, the chips will be randomly programmed with the big bopper messages; some lucky schmoe will get to hear, at some point, "You've won a million dollars!" At this point, the chip "locks" and won't say anything else; in fact the chip locks for any winning message. Confirmation codes on the book and the chip guarantee their authenticity.
Obviously this won't be cheap. To cover the cost, the coupon book is not free, though the cost of purchase is less than the combined value of all the coupons.
Winners: Value of coupons, value (what little that might be) of the book itself after all the coupons are used up, and the tie-in audio messages along with the possibility of winning a million (for example) bucks.
Losers: Up front purchase cost makes this a dud in no-gambling or no-lottery states, and it's obnoxious as hell when the chip does its thing.
One last note: in order to be absolutely certain that the customer hasn't missed out on his million bucks, he has to open the book to every single page. The bigger the book, the more he's exposed to your ads. Diabolical, yes?