Scala (music software)
From Just Solve the File Format Problem
Scala is a free (and apparently closed source) GUI software tool for working with musical tunings and scales. It is scriptable using .cmd files.
Scala can export a large number of formats for use in other music software, but also has two internal formats. Happily, they are openly documented: .scl files describe scales, and .kbm files describe mappings from MIDI note numbers to scale degrees.
