XnView Software

I was previously using the Sony PMB product, however, it is really limited in the types of files you can view. It did, however, have one very convenient feature: The ability to view pictures in multiple sub directories while still keeping those sub directories separated from each other.

There was a simple bar between each sub directory, with the name of that sub directory above each set of pictures. This would be a very convenient option that I would like to be able to turn on/off as desired.

Yes, this is the method originated by Picasa and is quite excellent for interactive browsing... better for many purposes than the one-folder-per-view-approach used by the majority of image tools.

A non-trivial programming activity to create such a view, however.