Rune and Silver Surfer got the flip-book treatment for a one-shot deal. The story starts with the Rune side to about the middle of the book and then you flip it over and start reading the Silver Surfer side.
There are two other versions of the book, and although the book is bound differently the interiors seem to be the same. Each has the same Silver Surfer flip-cover.
These are fairly common on eBay. I picked up all three as part of a large lot of Rune books (he was featured in a number of different Ultraverse titles) for $15. I wouldn’t pay $15 for just the Silver Surfer books, though … $5, maybe.
The scan doesn’t do justice to the white Collector’s Limited Edition. It is one of the nicest-looking of all the Ultraverse books … pristine white, shiny cardstock cover with perfect squared-off corners.