Have sombody think of making verry nice money by using google vouchers to target their own site? Exemple: You give your friends vouchers to run a targeted cpm campain to your site. You are not violating any google roules, and you should make a lot more money than by usual cpc. For instance, I sell 50 111$ google vouchers for only 100$ or 100 google adwords vouchers for only 150$. Even if Google pay you only 30%, you invest 1,5$ and get 30$.