Kids, I am old enough to have written a DOS TSR in 8086 assembler! Sadly, you likely have no idea what I'm talking about. Suffice to say, I understand this article completely.
I also tied into the keyboard hooks so that I could build an entire decoy base with a single key press (just some simple buffer stuffing) along with a cool little "death blossom" attack.
Ahhh, those were the days ;)
I'm visiting from the world of Ruby too, yet I was deep in masm/tasm, 386 dos extenders back then :)
Without the pain of INT13 behind me, I doubt I'd have gotten so far.