Last week I visited Boeing's Everett, WA factory, and saw the 747, 777, and 787 lines. I couldn't take pictures and had no time for notes, but I did have a few observations/factoids that I wanted to record:

The tour was *not* free - it cost $16 if you reserved ahead of time, which I did. They do tours every hour or two, and my group filled two buses - probably 50 or 60 people in total.
The Everett facility is the largest building in the world by volume. Our tour guide said that last year someone in China opened a mall that's bigger by floor space, but that Boeing is expanding to get that title back too. I assume that that is a) hyperbole, and b) true nonetheless.
The facility employs something like 41,000 people on a daily basis. Fuck.
The 787 is pretty cool. It's made mostly of composites - presumably carbon fiber + epoxy + some mix of aluminum, titanium, ceramics, and other metals (there's a good explainer on its construction here). Its wings can flex something like 21 feet vertically during flight, giving it a lot more vertical compliance and presumably making the ride a lot smoother.
The 787 is significantly smaller than the 747. Boeing is proud of this, and scoffs at the Airbus A380's enormous size. They're trying to push away from the hub-and-spoke model, and encourage airlines to purchase more planes, which will fly a wide variety of routes at relatively high usage rates. Since it's really hard for airlines to make money when flights aren't full, this strategy seems to make sense - it's *really* hard to fill an A380 (they fit 853 passengers!), so why not just buy two or three 787s (242 to 335 passengers) and fly them fully booked?
Planes are purchased without engines or seats; those need to be bought separately, and Boeing will install them at the end of their production line.
I asked what engines Boeing uses, and was told that while the makers vary by model, Boeing typically uses a mix of GE, Rolls Royce, Pratt & Whitney, and CFM (a collaboration between GE and Snecma).
Interestingly, Pratt & Whitney (now a subsidiary of United Technologies), Boeing, and United Airlines all once shared a parent company: the United Aircraft and Transport Corporation. That company was disbanded in 1934.

I would *love* to know more about the 787 supply chain. The Japanese company that makes the prepreg, Toray, looks interesting. And obviously both Mitsubishi and Kawasaki (both big suppliers for Boeing) are fascinating as well.