Of course it's possible that the historical evidence of the Thurn and Taxis postal monopoly, including the website and the museum referred to in blue_enzian's writeup, was fabricated, and planted everywhere a Pynchon reader might look for it, by agents of Thomas Pynchon and/or Pierce Inverarity. It's even easier to pull off this kind of historical hoax on the web, where anyone can make an official-looking site. And is it coincidence that there wouldn't even be an internet without Yoyodyne technology?