AFAICS the only fonts immediately available to \lookup which are not more
easily accessible via \musicglyph are the myriad of braces of different
sizes. The Internal Reference suggests that font-encoding may be set to
fetaMusic, fetaNumber, TeX-text, TeX-math, fetaBraces, fetaDynamic, but the
glyphs in fetaMusic, fetaNumber and fetaDynamic are all available via
\musicglyph, and the TeX fonts don't seem to be distributed with LilyPond
and are not available by default on Windows.
Could someone please confirm this is correct. Werner?
Trevor