suEXEC is a solution if each user who wants to use the scripts will locally-install the script

Two words: hard links.

Then you still want some sort of authentication to ensure that not just anyone who happens to go to ~susan can manipulate susan's files.

Basic auth + SSL might suffice.

Playing games with sudo, elevated privileges, multiple scripts, etc. shouldn't be recommended. Chances are that someone trying to implement things like that without a solid understanding of the issues is going to create all sorts of holes.

Really, we should probably respond with the question, "why are you doing this?" Because, there's almost certain to be a better solution already built.

-sauoq
"My two cents aren't worth a dime.";