should be a study of black and white tones. chances are, if you didn't have to shoot it at least twice in black and white to get what you were going for, then it doesn't work.
or maybe not. just explore what kind of interesting images you can get out of a tonal range in greyscale.
http://www.flickr.com/photos/peterlevi/7006024005/
http://www.flickr.com/photos/peterlevi/6653411623/