Japanese scientists have managed to create an isolated magnetic 'bubble' without having to apply a magnetic field (Science 284 1969). The breakthrough could lead to new forms of magnetic memory. Magnetic bubbles are small regions of material in which the magnetization points in a different direction to the surrounding region. In the past it has been necessary to apply an external magnetic field to create magnetic bubbles, making them unsuitable for data storage applications. However, Tomoteru Fukumura of the University of Tokyo and co-workers have observed the spontaneous formation of magnetic bubbles in a lanthanum-strontium-manganese-oxygen alloy, La_1.4Sr_1.6Mn₂O₇. However, the bubbles only form at temperatures around 70 Kelvin. The next challenge is to get the technique to work at room temperature.