The Verge article links to an incorrect Twitter handle, it should be @youtubeartifact (and not youtubeartifacts with an 's'). [0]
There's a great tutorial/article here [1] on datamoshing / I- and P-frame hacking. Searching for 'datamosh' or 'datamoshing' on YouTube will return many good results.
Finally, I also recommend checking out a great glitching iOS app (which does photo & video), Glitch Wizard [2].
[0] https://twitter.com/youtubeartifact
[1] http://forum.glitchet.com/t/tutorial-make-video-glitch-art-h...