I have one kid that loves to do mazes, so when I was designing their bedroom I originally was going to paint one wall a giant maze with navy chalkboard paint and white paint (and lots of blue painters tape). It would have looked someting like this...
My design for their room has changed, but I still love this idea.
Just think of the minutes of entertainment it could provide (I say minutes because my kids rarely stay still for more than an hour).
Mazes give you a great graphic punch and pattern, and can almost be done to resemble wallpaper. I found a site full of free maze patterns here.
Now just picture them in color..
These would also make cool patterns for rugs, tabletops, floors...
The possibilities are endless.