I've got lots of different email addresses, all in the same domain - partly because of having things like 'support@...', 'questions@...' etc on my website, and partly because I always give a unique email address when registering for things (eg 'telegraph@...' when registering for the Telegraph's website). Because of this, the best spam indicator for me is when the same email has been sent to several of my addresses. Does anyone know of a spam filter that works on this basis??
It would seem to be trivial for an ISP to filter out spam based on either (a) looking for emails being sent to thousands of their users at once, or (b) looking for emails being sent to dummy 'honeytrap' addresses, or (c) both. There would be a huge market for guaranteed spam-free hosting - why don't they do it???
There would be a risk that bulk email from 'legitimate' sources like Amazon might get killed too, but the honeytrap addresses shouldn't ever receive those ones...
cbl.