Those WordPress users interested in stopping sploggers and their ilk from scraping/leeching their content might like this plugin.
AntiLeech helps prevent content theft by sploggers.
AntiLeech does not prevent the splogger bots from accessing your site. It produces a fake set of content especially for them that includes links back to your site (and mine, too, ok?) and sends it only to them. When they steal this content, it appears online just like normal, except now you've turned the tables on them and have provided them with useless content.
I've been using it for a couple weeks now and am quite pleased. It detected the Pittsburgh News (not to be confused with Pittsburgh Bloggers) user agent and I have instructed it to deliver gibberish to that agent.