That's where the throbber goes. You can find the images in the WB folder, you can recolor them the same color as the toolbar behind it to make it look better, but you cant make it go away. Deleting them will only make the windows flag show up in it's place. (so I've been told)
The images are: shell_throbber_large.bmp...and shell_throbber_medium.bmp.....and shell_throbber_small.bmp
