One thing I do from time to time is share a folder structure in many ways. This could include HTTP and AppleShare both (especially using SharePoints or equivalent to share a folder structure separate from the user's Public Site). However, if I allow Directory Listing for that folder structure, I end up with that ugly "Icon?" file, assuming that I added my own, more pretty or informative icon to any of the folders in the Finder. So, I looked up the correct directive to hide any file/folder pattern in Apache, and blocked that darn "Icon?" file from showing as follows:
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