This moon looks even more like it's made from green cheese than ours does, but it's not. Lame. Io, the innermost moon of Jupiter, is the most volcanically active body in our solar system because of gravitational "tides" exerted by Jupiter and its other moons. And the constantly flowing lava gives Io's surface frequent makeovers.
This image was created with data from NASA's Galileo spacecraft collected in 1996. I0's appearance has presumably changed a lot since then, but there are still cool things to notice in this image.