Browser settings to block css and images

"If you use Firefox, you can apply your own CSS styles to all websites using the userContent.css file in the chrome folder in your profile folder.

You could add the rule:

* {background-color: white !important; color: black !important;}

Which would make everything apart from images (and maybe a few other things like borders, which could always be added to the rule) black on white. Then you could turn images off in the Content section of Firefox's Options/Preferences.

You could also Google CSS Reset for inspiration for more rules (you'll need to add !important to any rules as above to override the site's CSS)."

you can use the web developer toolbar on firefox to do it page by page, but i think you want to do it for all pages, so it might not be the best option.