[_yp]

This is one of the finest pieces of open source software that I've ever seen. The documentation is very good and even succeeds at making LaTeX accessible to non-technical people.

I've been using it for years for pretty much everything that other people would use LibreOffice or Office for.

[colanderman]

Not many pieces of OSS are on my list of "would continue to use even if all competing commercial offerings were open-sourced". LyX is on that list, beside Inkscape and Postgres.