ar_mailer allows you to queue ActionMailer emails in the database that will be sent with a separate process. ar_mailer gives drastic speed-ups when you need to send many emails.
To install ar_mailer:
sudo gem install ar_mailer
You can also download ar_mailer from Rubyforge:
http://rubyforge.org/frs/?group_id=1266&release_id=6548
For instructions on how to convert from the regular delivery methods to using ar_mailer see:
http://dev.robotcoop.com/Tools/ar_mailer/
ar_mailer-1.1.0 follows quick on the heels of ar_mailer 1.0. I've got several important features and bug fixes:
== Features
* Added --chdir to set rails directory * Added --environment to set RAILS_ENV * Exits cleanly on TERM or INT signals * Added FreeBSD rc.d script * Exceptions during SMTP sending are now logged * No longer waits if sending email took too long
== Bugs fixed
* Fixed last send attempt in --mailq * Better SMTP error handling * Messages are removed from the queue on 5xx errors * Added Net::SMTP.reset to avoid needing to recreate the connection