I occasionally receive emails related to production support tasks which must be acted on immediately. I'd like to be able to create a rule to play a custom sound when I receive one of these emails.

Since I can use rules to mark them high priority, another option is just having a different sound for high priority emails.

It would also be nice to have an option to always play this kind of sound over my system speakers. That way if I'm not wearing my headphones or I step away, I can still be alerted.