Hi Wondering Why. I just typed a belated reply ... This was an intriguing question and I hadn't the slightest idea what you were on about .... and we had a bloody power cut ... So: Start again
http://www.greece.k12.ny.us/taylor/tips/thumbs_db.htm Should explain a bit about Thumbs (Thumbnail) files, but I also discover Thumbs is something you can use in Firefox for searching for porn sites ...alledgedly but I think that is not relevant
I guess it's a windows thing. I did a LW search just now for thumbs and got piles of results for db files , so it seems like lot's of people are sharing these. It seems they are hidden by default, which might explain it.
Heres another link that looks very useful.
http://www.ftpplanet.com/ubb/Forum8/HTML/000174.html and follow the link in the top post
I am not sure why you should have one of these in your share folder unless you share images ... anyway I hope this helps