AnKsT wrote to mention an article on NASA's site about creating and manipulating glass in space. From the article: "In microgravity...you don't need a container. In Day's initial experiments, the melt--a molten droplet about 1/4 inch in diameter--was held in place inside a hot furnace simply by the pressure of sound waves emitted by an acoustic levitator. With that acoustic levitator, explains Day, 'we could melt and cool and melt and cool a molten droplet without letting it touch anything.' As Day had hoped, containerless processing produced a better glass. To his surprise, though, the glass was of even higher quality than theory had predicted."