Fortune is reporting that Google engineer Gokul Rajaram is leaving the Googleplex for a stab at his own company. Rajaram's greatest achievement? Oh, this little thing called AdSense, you heard of it? The ad system that places Google ads on blogs and Web 2.0 apps, keeping them financially viable against all business logic? After being hired in 2003, Rajaram supposedly worked to create the ad publishing network which now brings in, Fortune writes, "one-third of Google's revenue." Let's get this straight, people.