UPEI's professor Weale offers 70% to anyone who doesn't come to his classes. (CBC news story).

My policy is subtly different: Come to all my classes and I'll teach you all you need to know to get 100%; come to none of my classes and I'll teach you enough to get 0%.

The fine print: Of course to get 100%, you not only have to be taught, you'll also be expected to learn.