Evgeny Morozov argued in Slate last week that search engines could do more to warn readers about kooks online. Among other things, he cites to a recent article in Vaccine that details the tactics of anti-vaccine denialists. Morozov points to Google's special treatment of certain searches, such as "ways to die." Perhaps an alert can appear when one searches, "should I vaccinate..."
This assumes that online search engines will always be run by people who are not kooks, won't benefit from the activities of kooks, won't be intimidated by kooks, or just won't sell out to kooks. Be careful what you wish for.
I wrote a reply to Morozov on my blog the next day. I think his idea is at best unnecessary (third parties are already putting warnings like this in place using AdWords) and at worst a recipe for new conspiracy theories.
Morozov showed up in the comments of the post and comments further. Check it out here at the skeptools blog.