[TYPO3] restricting doc download

[pesz at pesz.hu]

Hi all,

I am looking for a way of restricting access to documents on the
frontend, regardless of usergroups' authorities.

I'd share lots of documents linked on pages. When user clicks on a link
of a document, would have to enter the password for the document, then
would be able to download it. Another document, another passwd.

Therefore I'd upload a document, set up a passwd, then share the passwd
with anyone i decide to let download it, regardless of any other user 
or usergroup settings.

Any idea is welcome,
arpad