What do you think of Crake’s idea to destroy most humans on the planet via distribution of BlyssPluss? Is he evil? Or... is he good for wan:ng to cleanse the earth of the destrucive nature of man?

Crake uses disease as a weapon of mass destruction. Crake's widespread distribution of his masked virus results in the death of almost the entire human population. Crake is not the only one to use disease as a weapon. Crake himself accuses pharmaceutical companies of inventing diseases and cures simultaneously in order to maintain a high demand for their services. Although one could consider this use of disease a swindle, it is also a powerful capitalistic weapon.

Finally, disease is subversively used as a cure to the problems of humanity. By inflicting a lethal disease on the world's population, Crake hoped to remove hunger, war, jealousy, crime, rape, and a host of other undesirable conditions of the human experience.

I personally would liken Crake to Hitler.