This project combines the architectural interest of crown molding with the soft glow of indirect lighting, whether it's along one wall or all the way around the room.
The project is no more difficult than a standard installation of crown molding—in fact, it's easier because you don't have to worry about fitting the molding tightly to the ceiling. Ripping the nailer strip is an additional step, but it's an easy task if you have a table saw. No saw? Visit a local cabinet shop and you may be able to get the strips cut for a reasonable cost. The 1-1/2-inch thickness of standard 2x lumber produces the right nailing strip height for the 4-inch crown chosen for this project. If you downsize to a 3-inch crown, cut the strips from 5/4 stock, which measures about 1 inch thick.
Paint the inside of the lighting trough to maximize light output from inexpensive rope lighting. You'll find the painting is easy because you apply it before installing the components.