Los Angeles started offering a $3.75 rebate on every square foot of grass replaced with a drought-friendly landscape. The drought is a boost in business for local conservation entrepreneurs. Frederic J. Brown/AFP/Getty hide caption

itoggle caption Frederic J. Brown/AFP/Getty

The Speck air quality monitor costs $200, but is available to all through Pittsburgh's public library system. Carnegie Mellon University CREATE Lab hide caption

itoggle caption Carnegie Mellon University CREATE Lab

A bird covered in oil flaps its wings at Refugio State Beach, north of Goleta, Calif., on Thursday. More than 9,000 gallons of oil have been raked, skimmed and vacuumed from a spill that stretched across 9 miles of California coast, just a fraction of the sticky, stinking goo that escaped from a broken pipeline, officials said. Jae C. Hong/AP hide caption

itoggle caption Jae C. Hong/AP