HTML::Mason is a full-featured web site development and delivery system. Mason allows web pages and sites to be constructed from shared, reusable building blocks called components. Components contain a mix of Perl and HTML, and can call each other and pass values back and forth like subroutines. Components increase modularity and eliminate repetitive work. HTML::Mason is most powerful when used in conjunction with mod_perl, but can be used in standalone applications as well.
The SeaMonkey project is a community effort to develop an all-in-one Internet application suite. It contains an Internet browser, email and newsgroup client with an included Web feed reader, HTML editor, IRC chat, and Web development tools, and is sure to appeal to advanced users, Web developers, and corporate users. It uses much of the Mozilla source code powering such successful siblings as Firefox, Thunderbird, Camino, Sunbird, and Miro.
ClearSilver is a high-performance, powerful, and language-neutral HTML template system. It enforces a separation between presentation code and application logic which makes writing, debugging, and maintaining Web pages easier. It can be used from C/C++, Python, Perl, Java, and Ruby. It runs on Windows and Unix.