[Catalyst] Suggestions for sending email from cron job using 'Catalyst' templates?

Put the logic in a model class that reads a config shared with but
independent from your controller so you can run it outside of Catalyst.
This article outlines how to do this
http://www.catalystframework.org/calendar/2007/14
If you need any web transaction details (c.user etc.) capture them at
request time and put them in an item in a queue (using ActiveMQ or similar).
Then in your cron script step through the queue entries, unpack the details
and do the template merge using TT2 before sending using Mail::Sender or
Email::Stuff or whatever.
You don't really need the Catalyst controller framework up and running to do
that.

Regards, Peter