<p>I have a custom control that inherits from WebControl and implements IValidator, but I also want to have a property for ValidationGroup.  From research, it appears I need to inherit from BaseValidator to do so.  Can anybody provide a successfull example from a ASP.Net custom control that implements both BaseValidator and IValidator?</p>

Ultraedit
is my favorite text editor and it is advertised as having good Unicode support
http://www.ultraedit.com/support/tutorials_power_tips/ultraedit/unicode.html
.
It has the find / replace / regex features you're looking for as well as almost every other feature I have ever needed.