Woofy - Woofy is a pretty neat webcomic downloader, designed for simplicity and ease of use.
CDisplay Ex - CDisplay Ex is the most used comic book reader.
yawr - YAWR is a webcomic reader that connects to a webcomic of your choice (dynamically extensible via...
YACReader - Download YACReader for your platform. Windows, Linux, MacOSX. And enjoy you comic books cbr cbz with the best comic reader.
ACMEreader - This comic viewer / comic reader lets you read your daily comics with ease.
Tachiyomi - A free and open source manga reader for Android.