TimeZones  

This package allows to add time zones to your site. User name and password protected admin area to add time zones, offset, display position, and date/time display. Language file in English included, easy to translate into other languages. Two different display files to include in column or on main page.

Hosting Requirements: Unix/Linux
Price: $9.95

   Difference between dates  

This is a simple script to calculate the difference between two dates and express it in years, months and days.

Hosting Requirements: PHP
Price: Free

   LastUpdatedTrick Function  

Do you want to make your website appear newly updated, even when the last update dates weeks back? Instead of showing today's date (which will make visitors suspicous) you can date your last update just a few days back using this function.

Price: Free