Eh.
My opinion as a designer is that those aren't good for anything but borders or wallpapers on your desktop. You can't put text on things SO colorful. It just wouldn't show up very well, no matter what color you made the font. A picture on top might be ok, but only if the picture had a decent border on it, I would say.
You could, however, place a solid color rectangle in the center of each one, so that maybe...20-30 pixels around each edge is visible, so that the pattern makes a border. Then you could safely put whatever you wanted in the solid part.