I think the official category of this one is "graphic novel", but it's not really great at that. What it is, is an extremely eccentric illustrated history of Victorian England from a very specific point of view. It's made up of a bunch of mini-stories covering various topics (from financial crises through Boolean logic), set in an alternative universe that somehow emphasises how crazy Victorian England was. There are copious footnotes, and even more copious endnotes, and then a super-serving of appendices. The cartoons are almost incidental by the end.
It appears the whole thing started as a joke, turned into a website, and then became a rather beautifully-produced book. When it comes to technical details Ms. Padua sometimes slips, but her historical scholarship is pretty hardcore (Yay, Google Books, it seems). The result is rather wonderful. Lovelace and Babbage would clearly have fit in perfectly to the dot com era.