Polyline Offsets (Tip #1975) from Stanley Pijl, is a timesaving tool for those who do drawings that contain multiple parallel polylines. Instead of running the Offset command for each parallel run along a centerline, use Ploffs after loading it in Visual LISP. You can add multiple offsets from the centerline by supplying the distances from the centerline or relative to the last offset created. This makes highway layouts a breeze and provides a nice demonstration of commands and logic combined to increase productivity.