Pilasters and Dentils
Here's a glimpse of a well planned, functional, and architecturally designed layout, using pilasters, and dentils on a crown moulding. The pilasters and dentils mesh together well, along with the window header moulding and window trim surround (left), and dormer with arched an moulding. Adding dentils to large cornice mouldings adds an air of prestige to the feature, as well as making it more interesting to look at.
In addition, you can tell the architect had throughly planned out his design as the lighting in the soffit is evenly spaced between the edge of the crown moulding and the outer soffit edge. Many designers and home owners don't realize that adding a crown moulding in the middle of a job means you need to offset your lighting so that the moulding doesn't end up covering the light.
Also of note is that flashing between the wall and roof to prevent water intrusion, similar as to what should be done with EIFS walls.