GonVisor is a surprisingly capable comic and image viewer.
The program's standout capability is probably its ability to open and view comics (and anything else, really) in the usual CB formats (CBR, CBZ, CBA, CB7). Just open a file to see the opening image and a list of pages. Set your preferred viewing options - you can run full-screen, single or double page, zoom in on images, rotate them, even improve them by optimising colours - and you're ready to get started.
GonVisor includes a lot of navigation options, too. There are keys to go to the next image, for instance, or the previous one. You can jump straight to a particular image (or page) number. Bookmarks allow you to return to favourite images later, and if you've several CBR/ CBZ files in a folder then you can jump to the next or previous one with a keypress.
You don't read digital comics? You've never seen a CBR/ CBZ file? That doesn't matter, because you can also use all GonVisor's abilities to view images in folders, or archive files. (And there's even a beta option to view the images in a PDF file, although you'll need to install and configure another tool before it'll work.)
Please note, while GonVisor is free it will ask if you want to install a couple of additional items (toolbars and so on) during setup. If these don't sound like something you need, though, just clear the relevant options during setup and you won't get any unwanted surprises later.