If your employees don't keep their work areas as tidy as you'd like, take a tip from Max DePree, the chairman of Herman Miller Inc., today a Fortune 500 office-furniture maker with sales of more than $700 million. Back in the 1950s, when Herman Miller was a midsize company, DePree discovered a way to keep the buildings neat that worked better than nagging or giving orders. The secret: holding open houses for families. Herman Miller started the practice to make workers' families feel part of the company, but DePree noticed that they had a nice additional effect. Offices and work spaces would suddenly mysteriously get a good, thorough straightening, as employees prepared for their family guests.