Better climate models are key to understanding how best to protect the environment and food production, but they require massive computing resources. You can help. Climateprediction.net allows researchers to parcel out simulations to computers that are online but not being used to full capacity. More than 96,000 idle computers in 138 countries have already been tapped to run thousands of simulations. Each participant receives a unique task, which could take days or months to complete. Current projects include models of atmospheric and oceanic forces acting from 1920 through 2080. Interested? Log on to www.climateprediction.net and download BOINC, a software platform that allows you to volunteer computing power for a range of scientific ventures.