This Perl script checks the "Last Modified" date and time of a file. You can choose the display formats. SSI needed. It has a big advantage over other methods as it can be used to check on a file placed outside the root directory.
A Bit Like Clockwork is a simple little CGI application for displaying the current date and time to visitors of your web page. The time/date is called via SSI. You may set a server offset for both Daylight Savings Time, and Standard time. This program runs under use strict, and -w and does not contain any cargo-culted code that so many other programmers have copied from certain clock scripts and used in their own incarnation.