I heard about this from the register (www.theregister.co.uk) Monday and download the software. It's great. As of this morning over 90,000 users were hitting back at the spammers. The idea is to make it too costly for them to run their sites and they close up shop. I don't see how this will slow the web down in the long run. If we could just close one of them down the amount of spam that stops will more than offset the traffic caused by this effort.
This method looks like it is being accepted by the general public. I only hope that something positive comes about from it and not just more net slow-downs in the long run.
Spammers get taste of their own medicine http://news.ft.com/cms/s/cd592a7a-433e-11d9-bea1-00000e2511c8.html