[[WMG:Uncle Enzo is Y.T.'s father]]
Really, it makes sense:
* When the two first meet, Enzo seems a lot friendlier than you'd think he'd be to someone who merely delivered a pizza.
* Towards the end, he's got a new skateboard that he says he wants to give Y.T.
** Surely he's just very grateful because she saved [[TheMafia CosaNostra]], and hence Uncle Enzo, alot of trouble and face by delivering Hiro's pizza at the start of the book? This being the mafia and all one would hope they'd want to keep up their image of rewarding loyalty and good service. And why would someone like Enzo have romantic relations with a drudgeon working for the Feds?
** If Uncle Enzo is her father, then wouldn't he have seemed a bit familiar to her? Y.T. is not a character who never knew her dad; late in the book, she recalls how her dad left her and Mom. If she ran into her dad again, she'd probably recognize him.
** Grateful is one thing, and I can write off the skateboard for that. But he seemed genuinely excited about it, as a gift. Moreover, he gave her his dog tags. That's not the kind of thing you just give someone who did you a relatively minor favor (yes, pizza delivery is serious business, but that seems to be a DisproportionateReward).
** I also got the strong impression that Uncle Enzo's behavior implied he was YT's father, including the comments he made about YT's mom that sounded vary familiar. As for the mention of YT's dad walking out, I'd always assumed that Enzo was YT's biological father, either from an affair or from before YT's mom got married. It's easy to see the two of them breaking up because "I'm in the Government, you're in the Mafia, we can't be together."
* Given the characters' respective ages, it's also possible he might be her ''grandfather''. We know nothing about her parents' backgrounds, and her Mom might've had to cut all ties with her Mafia relatives or in-laws in order to work for the Feds.
Alternately, he is actually [[ExactWords her uncle]] (her mother's brother) and he could never risk going to see her because of the constant surveillance her mother is under. He goes by "Uncle" Enzo to remind himself why he wants to be a nice guy, for his niece.
* Also either theory accounts for why her mother (and everyone else working for them) is under such extreme security from the Feds. It's a pre-emptive [[LawOfDisproportionateResponse Disproportionate Response]] by the Feds to keep her mother from acting on the familial relationship, The Feds being [[BigBrotherIsWatching the Feds]], they have decided that to be fair they will have [[BigBrotherIsWatching that sort of surveillance]] on all of their people, just in case.

[[WMG:"[[Music/RickAstley Never Gonna Give You Up]]" is the English translation of the nam-shub of Enki]]
If for no other reason than for [[spoiler:the Librarian to Rickroll everybody on the Raft]]. "You know the rules, and so do I!"

[[WMG:Y.T. is Miss Matheson, in ''Literature/TheDiamondAge''.]]
''Literature/TheDiamondAge'' takes place in the same universe as ''Literature/SnowCrash'', perhaps a century or so later. Miss Matheson is unusually old, well over 100 (Nell estimates her to be between 800 and 900, but that's neither here nor there). She used to be a skateboarder, and remembers an add about "Chiseled Spam" from her younger years. She had a friend who tried to teach her the martial arts (probably Hiro Protagonist). Sadly, this means that poor Y.T. became paralyzed "early in her career." But, at least she still grew up to be a cool old mentor for Nell.
* On the other hand, since being a courier is a life-long carrier, and she is well over a hundred at this point, [[JediTruth "early in her career"]] could be as late as 30 or 40, if couriers work their whole lives (only 30 or 40 percent through their carrier).

[[WMG: Uncle Enzo was training Y.T to be his replacement.]]
He constantly thinks and talks about how much he dislikes the younger members of the Mafia, and how they lack imagination, and spunk, two things that Uncle Enzo sees a massive amount of in Y.T.

[[WMG: Raven never had a DeadManSwitch on his bomb.]]
He was playing the Soviet side in a cold war of his own; implying (or in this case outright stating) that he had a Mutually Assured Destruction system in place (heh, [[FridgeBrilliance I only just noticed the acronym]]), without actually having one. He could have been wired up by one of Rife's techno-savvy Orthos, but it seems slightly unlikely. The most important part, to me, is that if he had had enough metal in him to send a message to the bomb when he died, he would have had enough metal to be seen on the radar near the end, since it was stated to be looking for metal in general and not ''just'' weapons.

[[WMG: Several of Stephenson's works are in a shared universe. Or, rather, polycosmos.]]
The most obvious is Literature/TheBaroqueCycle and Literature/{{Cryptonomicon}} because they are canonically the same universe. As a theory mentions above, Literature/TheDiamondAge and Snow Crash can also be a shared universe. Somewhere in between the events of Cryptonomicon and Snow Crash the [[spoiler:Advent occurs]] (Literature/{{Anathem}} spoiler), causing the governments to fall apart, creating the world seen in Snow Crash. Anathem spoilers again: [[spoiler: at the end of Anathem the Avout and the Saecular government mix together again, creating a second Rebirth and Praxic age. Downstream from that universe on Earth the technological revolution from this causes the invention of nanotechnology and the Diamond Age]].
* Alternately, [[Literature/{{Reamde}} T'Rain]] was a precursor to the Metaverse. (Literature/TheBigU and Literature/{{Zodiac}} could easily have happened beforehand) As The Diamond Age is likely in the same universe, it is possible that The Baroque Cycle and Cryptonomicon are installments of a single ractive series. Later, civilization collapses and is reestablished (Anathem).

[[WMG: Fisheye is deep in the closet]]

He is comically revolted that "Bruce Lee" (the pirate, not the actor) and his crew might be homosexuals; many homophobes in reality and fiction turn out to be closeted gay men themselves. Fisheye is awfully sassy for a "straight" guy. The passes he makes at Y.T., a girl probably young enough to be his daughter, are so obvious that there's a good chance they aren't real, but a closeted man's feeble attempt to [[HaveIMentionedIAmHeterosexualToday remind everyone around him how much he loves boobs]]. The Mafia has a history of homophobia, which may explain why Fisheye wouldn't want to let anyone know he is gay (even if he's not in denial about it to himself).

[[WMG: Snow Crash is a piece of historical fiction within the universe of The Diamond Age]]

The Metavirus stuff and L. Bob Rife's plot to rule the world probably didn't happen -- Snow Crash is true in broad strokes: the old nation states broke up due to electronic currency, corporations became superpowerful but eventually became subsumed by phyles because they were always designed to work under nation states. Snow Crash is like the Davinci Code of the 2060s -- a compelling little fictionalized conspiracy theory, made all the more plausible by the existence of the Drummers.