This is one I found last week while researching something else.
http://www.pspad.com/en/index.html a very nice editor that handles multiple programming languages along with plain text and html.
Some nice things I found in it:
HTML handling. A cool feature of this is it's "expand/compress" function.
Multiple file search and replace.
Built in FTP and server side editing.
There are also a ton more features and it is Free/donation ware.
I don't know ho0w folks manage to put what was obviously a hell of a lot of time in developing a product like this aqnd then give it away.
From a competing developer stand point, I hate folks who give this stuff away.
From a working developer standpoint; This sucker is going to be a part of my everyday toolbox because it reflects current reality where many of us are developing cross platform, multi language apps. I can bring my VB files, My Fox files, My ASP code, my php code and my html code all into the editor at once and switch freely between each one seeing syntax checking specific to the proper language, all at the same time.