.tag file question

[Doug]

I have found a file on a Jaz drive used to store downloaded files: simglafc.tag Another drive used only for local data has no .tag file. Where did this file come from? What is its purpose?

[Statica]

The tag file in general refers to the Tag Image File Format or TIFF. In addition in my experience I have come across a couple of other uses of .tag files one that has video files, or a multimedia file that uses a proprietary codec for compression/decompression/encryption/decryption; or some sort of a viewer that stores the TAG information say perhaps for slideshows.
The first thing I'd do in your case is check out the icon itself of the tag file .. does it appeared to be a registered filetype? Or go through your registry for references to tag extension [or file type views on Folder Options]. If that fails then just go through your list of multimedia viewers [grafix & video] there must be something that is cataloguing the contents of your drives.

HTH