There's a really similar story about Picasso asked by a lady in a restaurant to draw a simple sketch on a napkin. He does and hands it to her saying, "That will be [X] thousand dollars". Shocked, she says: "But that only took you 30 seconds!" "Madam", says Picasso, "It took me thirty years."
http://answers.google.com/answers/threadview?id=183998
http://www.snopes.com/business/genius/where.asp
There's a really similar story about Picasso asked by a lady in a restaurant to draw a simple sketch on a napkin. He does and hands it to her saying, "That will be [X] thousand dollars". Shocked, she says: "But that only took you 30 seconds!" "Madam", says Picasso, "It took me thirty years."