In February of last year, SPTH said "I'm going to sleep for a number of years", which turned out to be less than two. Interestingly, this is exactly the same phrasing that roy g biv used before he switched to writing Windows viruses. The number was five-and-a-half in roy's case, and, more, recently no-one has heard from him for months. That could be a good sign. Maybe he was so disappointed by the EOF-DR-rRLF zine that he gave it all up. I remain hopeful.
Anyway, back to SPTH. SPTH has written an article about the Chomsky Hierarchy and the Word Problem in Code Mutation. In his mind, "code mutation" is the technique of altering code to prevent its detection by anti-malware engines. Of course, code mutation can be used for other purposes, too, but SPTH is a virus writer, so viruses are his primary interest in this case. The "word problem" refers to the question of whether a given sequence of instructions was produced by a particular code mutation engine. Finally, the Chomsky Hierarchy describes the types of formal grammars that exist, from type-3
(simple) to type-0 (complex). SPTH's goal is to inspire virus writers to produce a type-0-based code mutation engine.  However, after a detailed description of the theory behind formal grammars, and no actual code, his conclusion is essentially "yes, it's really hard".
Yes, it is, and that's probably why we haven't seen it yet. In any case, he's making a large assumption about how we perform our scanning... but in the words of Forrest Gump, "That's all I have to say about that".
- Peter Ferrie