Catching cancer before it metastasizes, or spreads throughout the body, is one way to increase your chances of survival. Now scientists may have found a way to help even when cancer is already on the move, by using magnets to lasso cancer cells and drag them out of the body. Researchers at the Georgia Institute of Technology have shown that magnetic nanoparticles—tiny shards of magnetic metal, less than a hundred thousandths of an inch in diameter—can be attached to cancer cells, which can then be manipulated and moved with another magnet.