Swiss artist Gerry Hofstetter will light up the exterior of the National Cathedral (Massachusetts & Wisconsin Aves. NW, 202-537-6200) with colors and images from sunset to midnight on Friday, May 9, 2008, Saturday, May 10, 2008 and Sunday, May 11, 2008. The images will be projected directly on the south and west sides. Picnics are welcome and parking on cathedral grounds for this event is free. Check out the schedule of events to learn more.