I have similar function requirement. Based on your TRAMP method, I think
remote file are just can be transported through any protocols like HTTP,
for example remote file like http://example.org/test.org can be downloaded,
then append to org-agenda files list. This is just an rough idea.

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On Mon, Nov 20, 2017 at 3:54 AM, Eric S Fraga <esflists@gmail.com> wrote:

> On Sunday, 19 Nov 2017 at 11:10, David Arroyo Menendez wrote:
> > Hello Colin,
> >
> > org-secretary seems designed to manage teams. I want read agendas of
> > org-mode users, friends ... In Barcelona Supercomputing Center all
> > people is sharing the agendas to stimulate to the people to collaborate
> > in good ideas, I like this methodology, but I prefer use org-mode. Many
> > people in org-mode is connected with the science or creative
> > programming, perhaps is a good idea share the agenda between us.
>
> I guess one approach could be to make specific agenda files available on
> a remote server and use tramp syntax to add these files to the
> org-agenda-files variable?  (untested)  Of course, this would be limited
> to those access methods defined for tramp, i.e. ssh in practice, which
> might be quite limiting.
>
> A more general approach would be to export your agenda to Google's
> calendar or equivalent and share that and import any shared calendar
> using an ical access to these.  This is possible (my wife and I share our
> calendars that way) but not purely org.
>
>
> --
> : Eric S Fraga via Emacs 27.0.50, Org release_9.1.3-162-gde289d
>