pretty handy-dandy:
In the program directory you'll find *.rules files. You can edit them or add your own .rules files with specific names such as "date.rules" or whatever you like. Regulazy reads all rule files in its directory and shows them dynamically when they apply to the selected text in the work pane.
You can find out how to create your own rules (which is very simple - a line of text for each rule) in "How to edit rules.txt" file located in the program directory.

Blog:
http://weblogs.asp.net/rosherove/archive/2006/08/10/Regulazy-1.01-is-available-for-download.aspx
Direct:
http://tools.osherove.com/Regulazy/tabid/182/Default.aspx