I wrote an article for Cloth, Paper, Scissors magazine a while back about creating a very interesting journal page using black gesso.  It is a favorite technique of mine and love the look of it in my journals!

Jeannine Stein blogged about it at the Cloth, Paper, Scissors blog.
Here is a little of what she had to say:
In the article “Black-and-White Journal Pages” in the same issue of Pages, Jacqueline Newbold has a fantastic technique for prepping art journal pages and turning them into paper art. Start by painting a watercolor border on all sides of the paper. The beauty of this technique is that even if you’re not that familiar with watercolor, you really can’t go wrong. I sprinkled table salt on some areas of the wet paint to get a textured effect.