I'm pretty sure The Novelty of the Time Shadow Grave [http://www.tindeck.com/listen/gqqk] is completely serious (having read the thread where it was originally posted), but damn is it ever funny when dramatized (which is what that link is).
Plus it's relatively short, as the sheer mind-numbing stupidity of some poor misguided soul's painful attempt to write Warhammer 40,000 fan-fiction was mercifully never actually finished. I can only imagine how bad a full length version would be.
And lest you wonder, they are reading it exactly as it was written.