I have used it for a background:



To cover chipboard letters:



Layer punched circles behind other accents to give them more visual weight:

Punch (stars) or cut it (clouds) into accents:



Layered it as part of a flower:


Spritzed it with spray inks or color washed it with paint:

It's fun! And it's also an inexpensive way to add a sense of "history" and texture to your pages. I bought an old book at a second-hand store for $2. That book will last me a long time.
Give it a try and have fun!
I can't wait to see what you do with bookpaper!
Jana