BrokenLinkCheck - Free Broken Link Checker / Online Dead Link Checking Tool - find bad hyperlinks
Stylebot - Change the appearance of websites instantly. Preview and install styles created by other users on stylebot.me
Dead Link Checker - Check for broken links on any website
FreeStylerWs - Styles and skins for all popular sites in the web
LinkChecker - LinkChecker is a free, GPL licensed website validator.
Amino Editor - Amino is a Chrome browser extension for customizing web page presentation with user CSS.