The only thing I can think of is making a Christmas tree out of it. Do you remember how it is made - by folding the bottom corner of the page toward the seam and then making a crease. You just keeping doing the pages like that till it's done. Let us know what you came up with.

Sal

Well...I've used old books to create vignettes for miniatures or something unique/small for gifts. Usually I find an old book that fits their interests or the item(s)displayed. The covers can be opened or sometimes I put a window in them. You could do this with a phone book too.

Square up the phone book, place a heavy book on top. Paint white glue along the outside page edges and let dry for a day. Be sure the telephone book is square before drying.

Mark an opening on top page similar to a frame, for a phone book I'd draw this at least 1 1/2" from the outside. Use an sharp blade exacto and start cutting around the mark. You will have to do this a number of times to get through all the pages. Leave at least 1/2" of pages in the back. This creates an open box inside the pages.

Measure the inside of opening and cut cardboard or matte board pieces for lining top, sides and back. Glue these inside to create an open box.

Line the inside box with anything that works for you.

Since I use old books and they have a sturdy cover, suggest adding a cover to the phone book to support the shape. Make it in 3 pieces, front, back and spine. Use duct tape to hold these together, then wrap with a covering, suggest fabric of some type and glue only the spine if you want the cover to open.

Other than this idea, I can only think of oragami and then spray them.

I recall covering them with fabric and using them as a booster seats for young children.

Am I dating myself?

Well to be perfectly honest, I recycle mine in the city recycle container. But formerly, I took it to work to use, keeping the newer one at home. Not only to get phone numbers, but you can get a lot of lesson plans from the yellow pages.
I also used them to press autumn leaves and flowers.

My graandmother use to make dolls dresses out of TV guides
don't know how she made the sh=kirt and put a barbie in the middle
sprayed the skirt gold or silver for xmas