This is a very simple but useful application for viewing the sequence of bytes or bits in a binary file. I have modified my old bytes viewer and added the option to view the sequence of bits as well.

You can choose the start and end index of the bytes / bits being viewed.

This is how the application looks:

The application also supports dragging and dropping files into the form.

You can use it together with Fiddler by selecting a session and then choosing for example File - Save - Request - Request Body.... Then open it with the bytes viewer to view the sequence of bits and not only bytes as it is in HexView of Fiddler.

The source:

And the executable (requires .NET 2.0 installed):