htmLawed is a PHP script that makes input text more secure, HTML standards-compliant, and suitable in general from the viewpoint of a Web-page administrator, for use in the body of HTML 4 or XHTML 1 or 1.1 documents. It is a customizable HTML/XHTML filter, processor, purifier, and sanitizer. It can ensure that HTML tags are balanced and properly nested tags, neutralize code that may be used for cross-site scripting (XSS) attacks, and limit the allowed HTML elements, tags, attributes, or URL protocols.
Perl text2html is an HTML 4.01/CSS2 project that converts pure plain text files into very informative and professional looking HTML documentation pages. The text files require no markup whatsoever; just naturally written text. This utility predates the now similar Python-based asciidoc.