freanki

This widget shows the time since a specific date. You can enter text before and after the result.
You have to enter the date like this: 2012-01-31, so it’s year-month-day.
Thats all 🙂

Time since date

This Plugin provides a widget which shows the days, weeks, month or years since a specific date.

zlaxyi

This plugin allows WordPress to easily show customizable Erisian dates and time (decimal) instead of the standard Gregorian dates. No theme changes are required.
The Discordian Date Function plugin provides a widget which will display the current Erisian time and date according to the <a href="http://en.wikipedia.org/wiki/Discordian_calendar" rel="nofollow ugc">Discordian calendar</a>. This functional based on the Discordian Date plugin by Dan Johnson.
Also you can add the shortcode [today_ddate] in posts or pages for show the Discordian date of today.

Discordian Date Function

This plugin provides Erisian (Discordian) dates and time in Wordpress. Also provides shortcode and widget which displays the clock, current date accor …

Time since date vs Discordian Date Function