One of the problems when reviewing Cryptonomicon is that you could easily end up writing a short novel just trying to summarize it. Here's my attempt to boil the story down to its essence. 
 During World War II, Lawrence Waterhouse is a genius mathematician who is part of the effort to break Japanese and German codes, and his job is to keep them from realizing how successful the Allies have been by faking events that give the enemies reasons other than compromised codes to pin any losses on. Marine Sergeant Bobby Shaftoe had to leave behind the woman he loves in the Philippines when the war broke out in the Pacific and after surviving some brutal island combat, he finds himself assigned to a unit carrying out dangerous and weird missions that seem to have no logical goals. 
 In the late '90s, Waterhouse's grandson Randy is an amiable computer geek who has just co-founded a small company called Epiphyte that has big plans revolving around the booming Internet in the island nations of southeast Asia. As powerful people with hidden agendas begin showing an interest in Epiphyte's business plan, Randy hires a company in Manila owned by former Navy SEAL Douglas MacArthur Shaftoe to lay an underwater cable. That's just a sideline for Doug and his daughter Amy who primarily work as treasure hunters. When they make a startling discovery, it links the personal history of the Waterhouses and the Shaftoes to a lost fortune in Axis gold. 
 That makes it sound like a beach thriller or airplane read by someone like Clive Cussler, right? 
 But I didn't mention all the math. And code breaking. And the development of computers. And economic theories. And geo-politics circa 1999. And how it was ahead of the curve about personal privacy. And it's about a thousand pages long. And there's some other stuff, too. 
 Plus, Neal Stephenson doesn't feel the need to conform to anything close to a traditional three act narrative structure. He's also often the writing equivalent of Clark W. Griswald in the movie Vacation since he'll cheerfully divert his readers four short hours to see the second largest ball of twine on the face of the earth. 
 Sprinkled among all this are appearances by real historical figures like Alan Turing and Douglas MacArthur. So what you get is a book that should be a mess of infodumps and long tangets that ultimately don't have anything to do with the story. And quite frankly, the ending is kind of a mess, too. 
 So whenever I read criticism of Neal Stephenson, I shrug and concede that there are many things about the guy that should make me crazy as a reader. However, the really odd thing is that he doesn't. I've pretty much loved every book of his I've read despite the fact that I could list his literary sins at length. 
 What's great to me about Stephenson is that it's so obvious that he loves this stuff. When he takes up a whole chapter laying out the mathematics behind code breaking, it's his enthusiasm for the subject that helps carry my math-challenged ass through. He's not giving us elaborate histories or explanations because he did the research and wants to show off, he's doing it because he's a smart guy who is excited about something so he can't help but go on at length about it. 
 The other factor that redeems him for me is his sense of humor. No matter how enthused Stephenson is, it'd still break down in the delivery if he didn't pepper his books with some hilarious lines. Sometimes even his long digressions are done solely in the interest of delivering the funny like a parody of a business plan that includes gems like this: 
 "Unless you are as smart as Johann Karl Friedrich Gauss, savvy as a half-blind Calcutta bootblack, tough as General William Tecumseh Sherman, rich as the Queen of England, emotionally resilient as a Red Sox fan, and as generally able to take care of yourself as the average nuclear missile submarine commander, you should never have been allowed near this document. Please dispose of it as you would any piece of high-level radioactive waste and then arrange with a qualified surgeon to amputate your arms at the elbows and gouge your eyes from their sockets. This warning is necessary because once, a hundred years ago, a little old lady in Kentucky put a hundred dollars into a dry goods company which went belly-up and only returned her ninety-nine dollars. Ever since then the government has been on our asses. If you ignore this warning, read on at your peril--you are dead certain to lose everything you've got and live out your final decades beating back waves of termites in a Mississippi Delta leper colony." 
 It's also easy to overlook how these seeming digressions help build the entire story. When Randy is trying to retrieve some of his grandfather's papers from an old trunk, he gets embroiled in his family's attempts to divvy up his grandparent's belongings. Since the family is made up of academics a whole chapter becomes a description of a mathematical formula based on an x-y grid laid out in a parking lot that allows family members to place items according to both sentimental and economic value while Randy has to try to find a way to diplomatically claim the papers. There's no real reason for this scene, and it could have been cut entirely or boiled down a few lines about a family squabble. But the whole chapter is funny and tells us a great deal about Randy and his background by putting him in this context. It doesn't accomplish anything else plot wise, but it's the kind of scene that makes this book what it is. 
 Even as a fan of the way he works, I still wish Stephenson could tighten some things up. The goals of Epiphyte and Randy shift three or four times over the course of the novel, and the drifting into and out of plots gets very problematic late in the game. It also seems like Stephenson had a hard time determining exactly who the bad guys in the 1999 story should be. (view spoiler)[ The stuff with Andrew Loeb, a litigious asshole who once drove Randy into bankruptcy, showing up as an arrow shooting/knife wielding attacker wearing a business suit in the jungle at the end seems to come out of the blue since he's really only appeared in flashback form before that. Even though he's the lawyer suing Epiphyt there aren't any scenes directly showing him in action except for Randy viewing him from a distance during the raid on their server. And while most of the book seems to operate under the idea that the rich dentist is the main threat to Epiphyte, he suddenly tags out and a Chinese guy that we've only seen as a slave during WWII is revealed as the hidden hand behind it all very late in the book, yet we have no present day scenes with him. (hide spoiler)] 
 I should also note that although this is billed as a sci-fi novel as well as being nominated for and winning some prizes like the Hugo and the Locus, it really isn't. There's one small supernaturalish element that gets it that reputation, but I'd call it historical-fiction if I had to put a genre on it. 
 Even though this is a book that really shouldn't work, the great thing about it is that it mostly does, and it's just so damn clever at times that I can't help but admire Stephenson. 
 Related material: The Baroque Cyle is the follow-up/prequel to this that delves even further into the history of the Waterhouse and Shaftoe familes. These are my reviews to the three hardback editions, but those were such kitten squishers that it was also broken up into a longer series of paperbacks. 
 Quicksilver 
 The Confusion 
 The System of the World