Eighteen months ago, throngs of Filipinos gathered at a religious shrine for a rally that ended in the resignation of corrupt then-president Joseph Estrada. The massive turnout was widely attributed to mobile texting, with hundreds of thousands of Filipinos passing along messages encouraging people to attend. Now, the cell-phone-happy people of the Philippines are turning to text messaging to fight a different enemy: air pollution. The nonprofit organization Bantay Kalikasan, or Environmental Watchdog, has launched a campaign to get dirty trucks and buses off the streets of Manila, among the most polluted cities in Asia. People with cell phones are encouraged to report, via mobile text, any vehicles they see emitting black smoke; BK then sends lists of vehicles that have five or more complaints filed against them to the government agency responsible for issuing licenses to trucking and commercial vehicle companies, and the agency summons the owners for emissions testing. In the first two weeks of the campaign alone, 123 vehicle owners were called in. BK’s ultimate goal is to get the government to enforce its Clean Air Act, enacted in 1999, so that cell-phone owners can go back to texting their friends.