Speaking of Hypnotic Tales (in the last post), here is a large drawing that was published only in the limited edition hardcover version of that 1992 book. It was used for the endpapers at the front and back.
Below you can see how the printed version looked, at least at the back of the book.
In the front of the book there was also a signed bookplate which obscured part of the drawing. Plus the flap of the dust jacket hid parts of it as well.
Something else the hardcover version had that the soft cover version didn't: a quote on the inside dust jacket flap from the great Dan Clowes. The publisher (or the AD, can't remember) made the decision (mainly because of my design of the back cover) that there was room for only one quote on the back. And so even though Dan had graciously contributed his quote first, we went with the equally unbelievably kind quote from Gahan Wilson (which came in just as the book was about to go to the printer) as the sole quote on the back and the only quote on the softcover version. (I remember writing a letter of apology to Dan about that -- I hope he has finally forgiven me!)
Frankly, I was shocked that I had any quotes at all for my first book, let alone from two of my favorite cartoonists. In fact, they were the only two people I approached for a quote, so that was extremely encouraging. I have no idea if "blurbs" ever really help sales, but it certainly can give the author's ego a boost!