Hmm, maybe you’re thinking about somebody else? The guy I know of as putting lead in gasoline went on to put CFCs in fridges…

I don’t typeset music myself but I’ve heard that LilyPond is very good. It is based on LaTeX.

Great job!

I use Liberapay and have been pretty happy with it. Have found quite a few of the people and projects to which I would like to donate, but not all.

I use Runbox, and have for many years. Overall I’ve been happy with them. I think they have the features you are looking for.