Exif data is data that your digital camera records about every shot. The FxIf plug-in shows date and time, exposure settings, white balance, if flash was used, focal length etc.
FxIf appears to be a very good plug-in for FireFox. I just started using it and it works great on PhotoBlog images (not thumbnails). Most of the Exif data is shown if its there and hasn't been wiped out by an editing program.
Here's the link!
Enjoy!
Ted