My favourite is the company offering click farm services mentioned in that article, especially the testimonials:
'"Bill was putting a lot of pressure on us to dominate the web portal business, but we just didn't see how we could build our traffic quickly enough. We turned to Click Monkeys!!™ to deliver the uniques we needed to show up in the Media Metrix top 20. Thanks to them, I got my bonus, our site is on top of the charts, and Bill thinks I'm great!"
--Product Manager, MSN.com'

Besides that I always tell my clients not to rely on pay per click advertising which can be easily tricked. Only real "organic" positions through seacrh engine optimization can lead to real traffic.

Pay per lead or sale might be better but what is the lead or the sale on an purely informational site and how you want to track that if I bookmark the site and buy a month later?