The ability to identify "friendlY" links from known domains. IE - you describe the friendly domain list and it segregates the reporting.
In short - you could track links coming from your own link farms vs. the world pretty easily. Dumb idea, but useful for mining data. In short you could define your "friendly" domains.
I don't get why anyone would want this, and has so much traffic from link farms that AWStats doesn't already provide it.