Here is a literary genre I did not know existed, Bizarro Lit, as reported by Cracked.com. (I presume this web site has its origins in Cracked Magazine, a lesser-known competitor to Mad Magazine in my childhood.) Here we see perverse hybrids of other pulp genres.
This itself is hardly surprising. I cannot fix offhand when explicitly combinatorial or self-conscious genre-bending came into existence, but one can trace this tendency as least as far back as the last third of the 19th century. Consider various movements and genres over the past century and more— 'pataphysics, surrealism, Oulipo, alternate history, steampunk . . . All are outgrowths of certain time periods and social circumstances. Individual authors such as Hermann Hesse and Jorges Luis Borges also come to mind. I think also of Richard Brautigan's genre experiments in the 1970s.
Yet, it seems to me that, for those not entirely immersed in popular culture and its attendant historical amnesia, we live in a markedly retrospective time, returning to and reexamining the past, especially of the 20th and late 19th centuries. We live in a combinatorially self-conscious period. I suppose this is usually termed postmodernism. But whatever you call it, there is a looking backward and a self-conscious comparison with the different presuppositions and norms of the present. I'm guessing this is where steampunk came from. I'm also guessing that the appearance of Esperanto and Volapük in historical and alternate history novels at this time is no accident; this also reflects our self-conscious exploration of the social/cultural past. (I know an English professor and Esperantist who agrees with me on this.)
What we cannot know, if there is to be any future at all, what to look forward to that is qualitatively new. But then, we're in a situation at least partly described by Hegel:
". . . the Owl of Minerva takes flight only as the dusk begins to fall."