Things that may/do fail, and things I'd like to see added:

- Once you've changed to 2 page mode, the prefs dialog opens again
  showing the setting as 1 page (Seth Cohn)

- Add a 'memory' of the last page viewed, so it's easier to
  go back there. Maybe add a 'go to page' command too?

- Memorize the window size on exit too.

- Add an archive generator

- Prefetch next page(s) (Seth Cohn)

- Rotate pages (Seth Cohn) - This is quite slow or resource intensive,
  will look into it

- Maintain fit to window scale when resizing.

- A continuous page flow. (Ragnar Hojland Espinosa)

- Fullscreen and good antialiased (xavier.lacroze[at]gmail.com)

- Download zip files directly from an url (xavier.lacroze[at]gmail.com)