Well, as far as I can tell, without being slightly obnoxious (don't worry, it was still highly entertaining

), this guy wanted to install linux on his ipod (I did it with my old one.... never really understood the appeal.. nothing changed). Unfortunately, that program doesn't work anymore because the ipod has changed since the program was made. So this ridiculously smart 17-year-old goes and finds some obscure program that a guy in England created to control that clicking noise that the ipod makes. Then smart-kid goes and makes each click correspond to a different piece of information going through the ipod as it starts up, with longer amounts of time between clicks to mean different types of information (you know, 0's and 1's... that sort of thing). So now, when the ipod starts up, the program that starts it up is sending lots of information through the ipod, and so the ipod is clicking along with each piece of information. So, in order to see what all of these clicks mean, i.e. what exactly the program is doing, this guy puts the ipod in a sound-proof box, starts it up, and records the sounds it's making. Then he puts the recording onto his computer, uses yet another program to decipher the noises back into the information they represent, and voíla! he has the program that controls the ipod. So now people can make extra programs (games, utilities, etc.) that work on the ipod around this program.
Tell me if I'm completely wrong, but I think that's about it, in slightly more simple terms than the article...