I was reading the posts about starting to read digital comics and I have not found any referece about GonVisor viewer, I found it strange because I'm using it for many years. It is similar than CDisplay, quite simple and light, but GonVisor is a bit easier to use at first time and it has some additional features (manage and rate cbr files, cbr creation, printing features...).
www.gonvisor.comAnother one is YACreader. It has a plugin for browsing comic collections, some interesting visual effects... and it is also available for Linux and Mac! :O
http://code.google.com/p/yacreader/And MangaMeeya is another one that is not so known as CDisplay. I really like how it turns the pages
. I have not found its official website but it is easy to download using google.
We are lucky, there a lot of alternatives for reading Digital comics