http://upload.wikimedia.org/wikipedia/en/d/d0/I_was_a_Rich_Man%27s_Plaything_1947.jpg

and

http://upload.wikimedia.org/wikipedia/en/d/df/Roy_Lichtenstein_Drowning_Girl.jpg

are two that I like the look of, the preceders of the post modern art movements, what became known as "pop-art" These are two good examples, although they are about what is going on in the 50s/60s, it might not be totally clear to everyone.