We have all came across the arbitrage sites at adsense before. Those top8.bestsites.com similar sites, where they buy a click at lower price, and hope the visitors they sent will click the adsense on their site with a higher price. Yes, buy low and sell high, that's the basic of arbitraging.
In a post here few months ago, we spoke about how smart pricing and recent changes of adwords (quality score, landing pages algorithm changes) has affect those arbitragers. But they are not gone, to say the least.
And, there are better methods which is to buy cheap traffic from 3rd-tier ppc search engine for high paying keywords.
Well, action speaks louder than words, I gave it a try few days ago and all I can say, the result is 'phenomenal'. I cover my investment on buying traffic, for around 2.5:1, which is, the one dollar I paid to the cheap ppc search engine, I got 2.5 dollar back. All it takes is just some trial and error, keyword research, niche targetting, and boom

It almost is a no-brainer
Anybody else would like to share their experience on PPC arbitraging?