Are there ways to address global warming that are less costly than curbing fossil fuel use? You betcha, at least according to a new report by the National Center for Policy Analysis, which notes that new geoengineering technologies are now being developed to significantly cut greenhouse gases for a fraction of the cost of displacing coal and oil. One suggested strategy is aggressive reforestation, which alone could cut emissions by 20 percent over three decades. Other ideas include putting tiny silicon particles into the stratosphere to bounce solar radiation back into space, and seeding the ocean with iron filings to increase algae blooms that suck up CO2. These and other such proposals are now becoming a hot topic in the global warming debate.