Or to spam disqus comments on various sites. I always see similar spam bots with comments like "I agree with bob here. Let me also mention a great way to make 895 dollars a day from home".

Also more on topic I could see Rant being helpful for online language lessons or something. I remember exercises in grammar school where you would have to identify parts of a sentence(ex: possessive pronouns, transitive verbs, etc). I think it would be fairly easy to use Rant to generate unique questions for each student. Not sure how practical or useful that actually is, but it could be fun to make.