In a remarkable feat of expense-account wizardry, Chicago marketing executive Edgar Furness transformed a prostitute into 250 color copies Monday. Furness, who enjoyed a half-hour of sodomy with prostitute Chantel LaRue during a business trip to Dallas last week, magically turned the sexual encounter into a stack of colorful, easy-to-read pie charts created at Kinko's for a presentation to clients. Furness was reimbursed $58.93 for the tryst. 