WordPress.org

What is the point of this plugin?

Cache Time is meant to display the time that your website last cached the current page, for both you and your users benefit. There are many instances where users want the most current information, and this is an easy way to show how current that info is.

Is WP-Cache the only caching plugin that works with Cache Time?

Officially, yes. WP-Super-Cache may work, though I have not tested it.

OK, but what if I don't have WP-cache installed?

If no caching system is installed, the plugin simply displays the current time.