org-mode isn't just an agenda-making program. It can also export to lots of formats: LaTeX, PDF, Beamer, iCalendar (agendas), HTML, Markdown, ODT, plain text, man pages, and more complicated formats such as a set of web pages.

This isn't just some afterthought either; it's a core part of the system and integrates very well.

One file can be source code, automatically-generated output, task list, documentation, and presentation, all at once.

Some use org-mode as their preferred markup format, even for things like LaTeX documents. The org-mode manual has an extensive section on exporting.