Paris-based designer Christian Louboutin, whose pumps have graced many fabulous and famous feet, sued fashion rival Yves Saint Laurent over the use of the color red on shoe soles. "Mr. Louboutin is the first designer to develop the idea of having red soles on women's shoes," said the trademark infringement lawsuit filed in Manhattan federal court on Thursday.Since January, Louboutin said in the suit, he has asked ...