Sleazy Fork is available in English.
Can work on almost any webcomic/manga page, preloads 5 or more pages ahead (or behind), navigates via ajax for instant-page-change, lets you use the keyboard, remembers your progress, and it's relatively easy to add new sites
http://mangacow.co - Forward/Back doesn't work on this site...
Any fix for this? I just get a red stop icon for the image and end up having to disable it for the site.