I don't know if this program does, but it seems to be one of the more popular apps for file recovery (I just snagged it, as it's free at the moment).
A couple others that you may or may not have stumbled across can be found here and here.
Thanks, Matt. I checked the first two out, they don't support recovery across a network; the link to the third one seems to be broken.
Probably by now Mr. cow-orker has given up and spent an hour or two recreating the file. It was an audio file of some kind.
tanstaafl.