After the telephone attack, I go for the header. Many times you can track their IP, and file a complaint. More times than not, their account is closed. Thus costing them more money to open another. If they have a website, the next attack is to the host.
Many hosts also have anti spam rule, there again the account is closed.
More money out of their pocket. It may only make a tiny dent that can't even been seen, but boy do I feel better. Never underestimate a woman's scorn. You can fight back.