Surely, you've noticed that you see fewer suits at work or at business get-togethers these days - and more chinos. Business dress is becoming increasingly relaxed, especially at young companies. A survey of the 1997 Inc. 500 revealed that casual or "business casual" dress is standard at more than one-third of the nation's fastest-growing privately held companies. Roger Mody, CEO of the Inc. 500 company Signal Corp., a $55 million information-technology-services provider in Fairfax, Va., has seen his customers' attire become increasingly insouciant in recent years, so he's allowed his employees to dress more casually, too. "People are far more productive when they're casually attired," he says now. "They're more comfortable and more creative." Within five or seven years, Mody predicts, it will be an anomaly not to dress casually - "which I'm sure the suit industry is sick about."