ComicGuru is there, but a proprietary format...
Djvu, A competitor for pdf, as it works as virtual printer, with an impression compression ration (twice pdf by compressing in low res the backgroung and then the foreground in 3 different colors then compressing everything)
http://www.vstl.indas.de/http://www.vaagmaer.com/djview/index.html (qtopia port)
Proper standard viewers (Yeah!!!, nothing to convert)
http://linux.bydg.org/~yogin/#QComicBook uses QT !!!!!!!!!!!!!!
https://sourceforge.net/projects/comicmaster/ use Qt 4.1.2 !!!!!!!!!!!!
They both suport the windows Cdisplay (Comic Boor Reader) format (*.cbr, *.cbz, *.cba)
It's simply a zipped/Rar/ace archive containing pictures that has it extension renamed
All sources are availlable so if theses could all be compiled, that would be great, will try to do that myself since i got the virtual machine now but will take time...