Simple Comic 1.7 build 0167 beta now has a bundled Quicklook plugin for both digital comic CBZ and CBR files built in. Simple Comic is currently at version 1.6.1 on their webpage but if you go into the Preferences and click on the Beta Update Feed option under Advanced > Updates, you will be presented with the option to update to 1.7 the next time you launch the app. Once you install Simple Comic 1.7 beta, restart you Mac and you will now notice all CBZ/CBR files now have thumbnails and you can view them using Quicklook. While in Coverflow view, you will now be able to flip through pages without opening up the file too.

Digital comic files come in two flavors, CBZ and CBR. They are just renamed ZIP and RAR files containing JPG files. While Quicklook can look at JPG files, it cannot look into a compressed file for them. Over on the arstechnica forums, a user named gheritt has whipped up a Quicklook plugin that allows you to view CBZ files. It displays them inline similar to a PDF file. Only CBZ files work right now. There is no built-in support for RAR compression in OS X 10.5 so CBR files will not work, yet.

Download the file directly from here and install into /Library/Quicklook.