Reading comics on your computer or tablet is awesome. But if you would rather read them on a more eye-friendly screen — like your Kindle — Know Your Mobile has some instructions on how to make that happen.
You just need to grab your CBR or CBZ files, throw them into Calibre (the awesome ebook manager), and convert them to MOBI, which you can then copy to your Kindle.
There are some downsides: the image will (obviously) be black and white, and the comic pages will only be as big as your screen. As a result, this will probably work better with comics that are already black and white and produced on smaller pages. Manga in particular works really well.
Hit the link for the full instructions.
How to Read Comics on Your Kindle [Know Your Mobile]