The mailing list for listmasters using Sympa

[Amos <address@concealed>]

Is there a feature that I haven't discovered, or any thoughts towards providing a site-wide unsubscribe?  In other words, not only unsubscribe from a given list, but given the option to unsubscribe now and forever any list on that site. 

Though, I could see that some lists that were of an official capacity, say for employees, be exempt from the site-wide unsubscribe.

Amos