As a counterpoint my home mail server has no spam filtering at all, and I receive at most 10 items of spam per year. Instead I spend time tweaking fun stuff on

As a counterpoint my home mail server has no spam filtering at all, and I receive at most 10 items of spam per year. Instead I spend time tweaking fun stuff on my mail server, like setting-up X.509 user certificate-based authentication instead of IDs and passwords. And transparent on-server S/MIME [ de|en ]cryption using Anubis. Stuff that the big mass-market providers won't implement.