http://host.com/cgi-bin/prog/the/path
that results in the program
/usr/web/cgi-bin/prog
being run with PATH_INFO set to "/the/path", then PATH_TRANSLATED is:
/usr/web/cgi-bin/prog/the/path
Rob McCool had some pretty good sounding use for this, but I don't
remember what it was and a fairly quick perusal of the www-talk archives
didn't turn up much.
Disclaimer: I never did bother putting this in my server so I may be way
wrong.