Comix is a user-friendly, customizable image viewer. It is specifically designed to handle comic books, but also serves as a generic viewer. It reads images in ZIP, RAR or tar archives (also gzip or bzip2 compressed) as well as plain image files. It is written in Python and uses GTK+ through the PyGTK bindings.
Version 3.5 includes new icons, a faster magnifying lens, more lossless JPEG operations, support for new image formats and some other new features and bug fixes.
Read more at http://comix.sourceforge.net