As usual on Unix systems, your .forward isn't limited to just email addresses; it can be used to, for example, run email through procmail. This page explains the environment that this mail filtering happens in at CSLab. We're not going to try to explain how to do email filtering in general; for that sort of thing, please talk to your Point of Contact (PoC) for help.
What email filtering applies to
This sort of general filtering works in your .forward, your .forward-nonspam, and in simple mailing lists.
Where email filtering happens
At CSLab, this processing happens on a machine called mailswitch.cs.
What programs are available where
Mailswitch has a number of standard mail filtering programs installed. Here's what's available and where you find it:
Please use /usr/bin/procmail. /local/bin/procmail and $MAILBIN/bin/procmail are other paths for procmail; they all run the same thing.
An in-depth reference for procmail is available here
Please use $MAILBIN/bin/vacation (a.k.a. /local/bin/vacation) This version of vacation knows to not autoreply to spam messages and so on. Don't be surprised if the environment variable $MAILBIN isn't defined in your login session on mailswitch (or elsewhere); it's only defined when these filters are being run.