Time and Date: Yahoo Calendar
Tim Akinbo (contact me)
Yahoo Calendar is a PHP class that generates URLs that can be used to add events to Yahoo Calendar. This is useful for individuals who send schedules by email to others.
In your email, you can hyperlink an image that says something similar to "Add Event to Yahoo Calendar". When this image is clicked on (provided the individual has a Yahoo account) the event would be added to his/her calendar.
Click here for detailed information about this class on phpclasses.org
Php Handleiding