I have to go with Andy Worhal and Mapplethorpe because they really pushed the envelope and opened peoples minds about what art can be.As far as composers Chopin,Tchaikovsky and Bach are the only ones I feel enough to stay awake.
Almost forgot big ups to Andrew Wyeth.He made what people considered art cool for a kid to look at.
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"I hope someone runs you over with their car."-guapo