The Internet Explorer 4+ equivalent of Netscape's about:mozilla.
If you enter about:mozilla into your Microsoft browser you will get a blue page (#000080 blue to be precise) with the title res://mshtml.dll/about.moz indicating where it came from.
If you type in res://mshtml.dll/about.moz you will get the same page.
The full code of said page:
<HTML>
<HEAD>
<BODY bgcolor="#000080" text="#FFFFFF">
</BODY>
</HTML>