Sxz
From Just Solve the File Format Problem
Sxz is a hybrid vector/raster image format intended for non-photographic images, allowing for non-rectangular shapes and holes. There is a JavaScript decoder which permits it to be used on the web even though it's not natively supported in browsers.
Identification
A Sxz files start with bytes 53 58 5A, or "Sxz" in ASCII.
