Spam Poison
We're all sick of those email-harvesting robots that are constantly traversing the web in the not-so-vain hope that they'll come across even more people to attempt to sell their dubious wares to. Most www users are, by now, aware that it's inbox-suicide to post your email address on the web unobfuscated.
This is why I was interested to come across Spam Poison. It invites website/blog owners to include a link on their sites which leads to a page at one of Spam Poison's other domains that contains a long list of fabricated email address, all at domains used by known spammers. This page, in turn, links to similar page, thus leading naive or impolite web crawlers into an infinite loop. This has the effect of keeping the crawler busy, while at the same time `poisoning' the spammers' databases with thousands of useless email addresses.
As someone who uses a web crawler for legitimate purposes, I must admit that when I initially came across the site, I was ever so slightly worried by the intentional luring of crawlers into infinite loops. However, they've been impeccable in their respect for polite crawlers, making use of both the robots.txt exclusion standard and the robots meta tag, meaning that my crawler wouldn't have been affected.
It's nicer still to notice that they actually followed the extremely simple robots.txt standard properly, instead of using some homemade `variation' of it, like an amazing number of other sites do.
Of course, an endorsement of the system wouldn't be complete without using it, so here's a little link for you all to not bother clicking on:
