We study malware propagation strategies which exploit not the incompetence or naivety of users, but instead their own greed, malice and short-sightedness. We demonstrate that interactive propagation strategies, for example bribery and blackmail of computer users, are effective mechanisms for malware to survive and entrench, and present an example employing these techniques. We argue that in terms of propagation, there exists a continuum between legitimate applications and pure malware, rather than a quantised scale.