Reynobond with EcoClean by Alcoa Architectural Products is a prepainted aluminum panel coated with a titanium-dioxide finish that, when exposed to UV light, breaks down organic matter and creates a hydrophilic surface; rain or dew can wash away dirt buildup on the surface. Alcoa estimates that 10,000 square feet of its panels can offset the smog pollution created by four cars each day. The panels are available in more than 30 colors. •