I'd be more than happy to explain how this script works at length, but to make a long story short, it functions best when there is a lot of text and when words in the text are *repeated* in different contexts. This script can be downloaded in a link at the bottom of the page, btw. It's handier that way.
Next time someone ridicules you on a forum or something, just wheel out the old Markov chain script and use their posts as stock for a hearty mockery stew. Why get yourself ground down by responding to a whole bunch of people by yourself with logic and reason, when dishing out dirt with the best of them is just a copy and paste away? They're too dumb to listen anyway.
I know these kinds of programs are extremely irritating because I wrote a cruder Python script for a persistent troll on another website that simply looked for keywords in someone's post and then tossed out a stock response from his repertoire. I then posted as him for a few hours. When he saw what happened, he got really pissed off and screamed until he was blue in the face, then stormed out like a little baby so he could sulk for a few days. I stumbled on the Markov method when I was reading about probability theory and it's way better because it can come close to a 'natural' imitation of someone's writing. A nonsensical imitation, to be fair, but one that hits too close to home.
I could simply copy/paste posts into a plain text file for each offensive poster to develop individual stocks or even merge all idiots into a single grotesque strawman. The possibilities are almost endless. See? Math is great.