3) Download all of Wikipedia
This is easier said than done. The online encyclopedia offers a way to download every Wikipedia page, picture, link, and even every user edit. However, this process takes a really long time. "Because of the size of some files (TERAbytes), downloads can take days, or even weeks, NOT including queueing time for your request," says Wikipedia. It estimates that downloading every English article will take 8 to 9 days.
Have a week to spare? The process starts at Wikimedia's Downloads page.
4) Turn to Google cache
Sure, Google links to websites, but it also takes a snapshot of many sites for later reference. This process is called caching. Former Adobe designer Philip Bump programmed a way to tap into that cache and retrieve individual Wikipedia pages. These saved articles can be several days old, but that won't be a problem for most pages. The entry on, say, Nicolas Steno won't change much over the course of a week.
Also, while the service works well in a pinch, most of the Wiki functionality is broken. For example, cross references all link to Wikipedia.org, which, of course, is blacked out today.