Amazon's Mechanical Turk service: pay someone to perform a task that can be done with a browser/PC. Rote tasks with no questions asked. Of course, there are charges involved. It looks to me like an easy way to build online reputation (and from the likes of it, that is one of its uses). Who knows what you could do with enough money and an army of Turks at your disposal? Maybe a way to cover your tracks or build plausible deniability by hiring a bunch of online impersonators?

Doesn't scale as well as a real botnet, but there are some possibilities here…