My girlfriend is amazed that I have the patience to read a 10-page wikipedia article from start to finish. I think I got that because I started reading newspaper articles when I was very young (strongly recommended to all parents).
It seems I'm a bit different than most other people here that I open and read new tabs as they come up, rather than opening them in the background and coming back to them (like a call stack instead of a queue), which helps for maintaining context. The articles that I tend to get large stacks on are math articles. I think my stack-based approach came from starting on math articles, because you need to understand underlying referenced concepts before you can continue with the rest of the article. Most other subjects aren't so linear, not even historical subjects, because an individual tends to participate in several events, an an event impacts several individuals, and you get all sorts of back- and forward-references.
On a related note, I have read references books cover-to-cover, including a selective dictionary (one that only includes difficult words, not "the" and "door"). Textbooks with excercizes are far better for retention, but I always stop instead of doing the excercizes.