Visual effects in games and movies is a direct usage. If I wanted to have a brick wall I could progressively melt with a large laser, I'd render it with an SDF

Visual effects in games and movies is a direct usage. If I wanted to have a brick wall I could progressively melt with a large laser, I'd render it with an SDF. SDFs are good for anything with volume, as mesh based rendering is intrinsically 'hollow'. It's not the only solution for things like that, there's also voxel and particle based rendering, as well as reasonable hybrids. It's just another tool in the toolbox.