bkmrkconv will convert Netscape's bookmarks.html file into a series of interconnected HTML pages which can be put online. The pages are heavily customizable and examples are included for a Yahoo-like portal. The program is useful for accessing your bookmarks from a remote machine or even just for making your links look prettier.
GPP is a general-purpose preprocessor with customizable syntax, suitable for a wide range of preprocessing tasks. Its independence from any programming language makes it much more versatile than cpp, while its syntax is lighter and more flexible than that of m4. The syntax is fully customizable, which makes it possible to process text files, HTML, or source code equally efficiently in a variety of languages.
The Guava tools are a set of Perl scripts for HTML pre-processing. You can create multi-page documents with contents tables, or use templates to give a consistent look to a set of pages. All output is passed through the C preprocessor, so you can use directives such as #include, #define and #if. There are also built-in macros for producing dates, cross references, etc.