A long time ago I talked about how great NDoc is.
Quick reminder: NDoc generates class library documentation from .NET assemblies and the XML documentation files generated by the C# compiler (or with an add-on tool for VB.NET).
I love the tool, I use it for all my documentation in .NET projects.
A few days ago, I had to make a Visual Basic 6 project. And one of the requirements was a documentation. Knowing about NDoc, I went looking for something similar for VB6. There are a lot off tools out there, commercial and free.
But VBDOX is the best in my opinion. It generates the same MSDN style documentation, as HTML with the possibility to compile it into a Windows Help file.
It can use an XML style of commenting, and quickly parses it and generates the documentation.
This resulted in a very nice documentation for my project.