piatkow - 5:59 pm on Jun 8, 2013 (gmt 0)
What you're talking about is called arbitrage. It used to be a great game, but Google doesn't like it.
One part of Google doesn't like it. Another part of Google actually sends Adwords vouchers to Adsense publishers.
I used up my voucher, made a fraction of the face value on Adsense and decided that arbitrage was a non starter in my sector. But that you G for a few extra pennies.