php(Reactor) is a PHP/MySQL-driven system of integrated web applications to encourage user interaction and easy website maintenance. Some of its main functions include: bbs/forums - supports flat, threaded, or ranked modes, simple yet powerful admin, moderator support, mailing lists; e-cards - supports graphical (gif or jpeg) as well as iframe and javascript cards; events - a place to schedule chat events, with option to restrict access to who gets to post events, or leave it wide open; polls - users can upload their own polls as well; and admin - allows you to control all functionality of your site through a browser interface.
iLogin allows you to password protect parts of your site. Visitors can only gain access to these pages if they sign up and provide you with certain information about themselves. Unlike some other systems, sign up is instantaneous - there is not need for an administrator to verify new users. Email address verification can be optionally performed. iLogin updates the .htpasswd file to allow new visitors instant access.
DCN DataFile 2004 is a PHP 4.0+ script designed to work without a database.
The html template file can be easily modified/replaced to integrate the solution nicely within your site.
No Database Required
Easy to modify/replace HTML template.
Searchable dB for an entry.
Column Sorting.
User defined page limit.
Overall very good hashed flat file interface model.
XCSSOR is a pure website engine (no content management system / CMS) written in PHP. It is totally based on XML content. No SQL Database required. All layout and design is XHTML and CSS and can be easily created (even in HTML). Smarty template engine.
YASEF probaby is the simplest email form you will ever meet while surfing the web for useful PHP scripts.
Once you have it up an working on your site it will let your visitors send you an email from a nice pop up window and without opening any email client.