ACal Project
A PHP calendar project that does not require a database server and is easy to install, setup, and use. [Open source, GPL]
Active Calendar
PHP class that generates calendars (month or year view) as HTML tables (XHTML-Valid). The layout can be configured using CSS, and JavaScript is not required. [Open source, LGPL]
Codewalkers.com - PHP Event Calendar
Includes a customizable look and feel and recurring events.
Easily Simple Calendar
Simple PHP calendar script that is easy to customize.
EasyEvent
A web-based application designed for ease of use and customizability. It provides event dates and information at a glance. [Commercial]
HIOX Monthly Calendar
A PHP/Javascript script to show monthly calendar. [Freeware]
Keith Devens PHP Calendar
A simple, but complete, PHP script to print out a calendar.
MicroCal
A calendar solution for dating or membership website. It allows running as popup, or being built in page or even in a form in script. [Free with crypted source code and commercial versions]
MyCalendar
PHP4/MySQL calendar featuring recurring entries, holiday calculations, optional categories, language packs, numerous search and display options.
PHP Availability Calendar
A PHP calendar script that shows availability of your rental based on calendar data. [Commercial]
PHP Calendar by Cascade
A customisable PHP 3/4 calendar class.
Project Based Calendaring System (PBCS)
An open source web-based system designed to be a useful tool for project managers or planners.
Proverbs Web Calendar
Shows a month format with a popup window detailing the events of each day as they are clicked on. The title and colors are fully customizable within a single file.
Schedule Organizer
Allows a customer to schedule an appointment via a company's homepage.
WebCalendar
A PHP application used to maintain a calendar for one or more persons and for a variety of purposes. In addition, the calendaring system is well documented. [Open Source, GPL]