SPOILER: It actually drives the climatic finale where Waterhouse performs an "epic hack" while in jail, modifying the linux kernel on his laptop to output the

SPOILER: It actually drives the climatic finale where Waterhouse performs an "epic hack" while in jail, modifying the linux kernel on his laptop to output the results of his cracking the encryption on the location of a cave full of gold as morse code in the form of his caps lock light going on and off. He also makes sure to write the code that will make these changes via hitting his space bar, which is translated to characters based on the amount of times he hits it, so that again the code to do the calculations is never exposed on screen. The only reason he is so careful about never exposing both the changes he is making to his laptop's code as well as the results of the calculations it runs is because Enoch Root visits him while he is in jail and basically warns him that people will be using Van Eck Phreaking to spy on the contents of his display. So really, it is actually one of the most crucially import bits of technology in the whole book.