Hyperlatex is a way to create documents that will look good both as printed text and on the web. It is not a general-purpose converter to take LaTeX into HTML. Rather it is a set of macro definitions that allow a user to write one document for two media and to have the output look good in both.

Hyperlatex is a set of Emacs macros, which can be used from within Emacs, or compiled and used independently. This also means that Hyperlatex is quite easily extensible, allowing you to deal smoothly with many unexpected situations.

The documentation to Hyperlatex does a much better job of selling the software than a little blurb can, in part because it's well-written, and in part because the documentation was written using Hyperlatex. So go look there.

Hyperlatex was written by Otfried Cheong, but is now maintained by others. The current version is 2.8.