Apps with 'Markup Converter' feature

Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library.

MultiMarkdown, or MMD, is a tool to help turn minimally marked-up plain text into well formatted documents, including HTML, PDF (by way of LaTeX), OPML, or OpenDocument (specifically, Flat OpenDocument or ‘.

It reads a text file with minimal markup such as bold and //italic// and converts it to the following formats (among others):

Textile is a lightweight markup language originally developed by Dean Allen and billed as a "humane web text generator". Textile converts its marked-up text input to valid, well-formed XHTML and also inserts character entity references for apostrophes, opening and...

SmartXML allows you to process XML files of any complexity and flexibly customize the set of extracted fields. Both relational and NoSQL databases are supported.

gnu source-highlight is a command line program that can be used to highlight source code, it supports output to many formats including html, ODF, ANSI and groff.