Not sure what to make of this one but...:
Lycos (that I now hate - see other thread) have come up with a screensaver that requests a page from a spammer's websites [but doesn't actually display it] - they reckon that if enough people download and use it it will clog up said sites (or use up their bandwidth allocation or cause a DOS).
More
here (a bit slow to load but includes a "annoy a spammer now" button to send instant data to a spamming site -- good stress relief).