Extract/Export Previews

Is there a way to extract or export preview files from the catalog? When the original files are offline a user is able to select items and perform an 'Action > Extract Metadata... > Image Thumbnails' action to save thumbnails to a folder. I have my catalogs set up create 800px previews and it would be great to be able to export/extract those from the catalog and save those to a folder as well. Anyone know of a way to do this? Or is this a feature request?