Hewlett Packard has a Web server. The source code is available for anonymous ftp . The documentation is available in PostScript format. A quick reference cheat-sheet for the scripts is available in hypertext and PostScript formats. Stuff on Emacs and XEmacs Emacs is about the best text editor to come down the pike.
Most AFPS developers use it.
It does more than just edit text. In fact it is hard to find something emacs does not do. The most popular version of emacs with AFPS developers is xemacs. Sunworld Online compares emacs and vi. Xemacs User's Manual Elisp intro page.