Of course as soon as I send the email I find:
http://zipios.sourceforge.net/
It appears rather inactive but then again how much has zip changed.
Quoting dulsi@xxxxxxxxxxxxxxxxxxxxx:
> I know I've seen game libraries in the past to allow a directory or a
> compressed directory file to be used interchangably. So during
> development you can have it unzipped to ease replacing individual files
> but can be distributed as a single zip/wad/whatever file. I can't seem
> to find an now. In particular I'd like one that handles zip (or even a
> library that does zip and doesn't handle a regular directory).
>
> Dennis Payne
> dulsi@xxxxxxxxxxxxxxxxxxxxx