When adding a filter through cPanel, we're given the rather vague "Destination" field.

I understand that "[e]xample[s] of valid destinations are 'Discard', '|/home/user/email.pl' or 'user@domain.com',", but what other options are there? If these are just examples, then it implies that there are a lot of options that could be used.

For example, I want any email sent to one email address to be BCCed to a second address. But I can't find a way to do this without writing a script to manage it; this is fine, but is unnecessary if there's a simple command that I could enter into the Destination field.