Ah yeah, what I was meaning was that afaik there's no way to tell what the image is without opening it or renaming it to its appropriate file type.
But of course, it's a pretty simple job to get a program to iterate through each file and move it to another folder, renaming it to .gif or .png appropriately.
Now I think, isn't this what
mess.be's custom emoticon stealer did? Although it allowed previews and stuff...
Direct Link (Might not work + reading CoC, been ages since I been here):
http://www.mess.be/pafiledb/pafiledb.php?action=download&id=301