I would like to write a very simple mailinglist and wonder if (and
how) this can be done with Rails.
I have usergroups and want to automatically make a mailinglist for
each group. eg a group is named testers . When you send a mail to
testers@mydomain.com all the users in the testers group should receive
the mail.
I don't know whether Rails can handle incoming mails?
First of all, i would not count on ActionMailer to handle large
quantities of mailing lists since it's none queued and the mails are
sent one after another.
i suggest you might consider a use of a 3rd party mailing list
service.
as for incoming mail, check out this page
http://blog.craigambrose.com/past/2008/2/9/respond_toemail_or_how_to_handle/
if you insist of using ActionMailer, try this to accelerate things a
little bit by enabling threaded operations.