Better ideas:
1. Sign them up for every spam mailing list and objectionable organization (like, say, NAMBLA) you can find. Their mailbox will overflow in no time and they might even get terminated depending on how thorough background checks are.
2. Call every delivery food joint in the area and make an order to be delivered at random hours for cash. Pretty soon, the restaurants will blacklist them and they won’t be able to get delivery.
3. Go on a home improvement website and sign them up for ‘more information’ - the solicitors’ calls and mailings won’t end for months.
4. Call the local Jehovah’s Witnesses, give them the victim’s information and tell them that you’d really like to talk to some people about God and would they please send some over. (Sorry if you are a JW, but your missionaries are great things to annoy a godless liberal with. And who knows? You might actually get a convert.)
5. Go online and sign them up for visits from the Avon lady, Amway reseller, etc., etc.
6. Sign them up for a free trial subscription to a competing newspaper.
7. Sign them up for any other free trial offers you can find.
8. Send over clowns.
9. Three words: Naked Singing Telegram. Select gender accordingly.
10. Sign them up for ‘free investment counseling.’
This actually happened to a notorious email spammer. The folks a slashdot.com got his postal address and posted it with the instructions that all of their on-line readers go to the local library and/or bookstore and remove the prepaid postage flyers from magazines and send them off with the spammers address. At the height of the email spammer vs. postal spammers war, the email spammer was getting 5 to 15 BAGS of mail a day. He pleaded with the USPS to stop, but they are required by law to deliver all mail. I'm not sure what the end result was, except the email spammer was doing the usual litigation threats if he ever found out who did it.
Do NOT post a yard sale advertisement on Craigslist. That would be wrong.
Do NOT post a hooker advertisement on Craigslist. That would be wrong.
Don’t forget putting their info on health insurance search sites. Those companies won’t stop bothering them for weeks.