HTML Match is the best HTML comparison tool for Windows available on the Internet today. Use it to analyze the changes between two revisions of an HTML file.
The M6.Net PR Quick Check is a extremely easy to use, free Page Rank checker tool that allows you to check the PR of a page or a web site and compare it with the previous PR of the same page. A very useful tool for webmasters.
Analyze and dissect webpages using Site Inspector; from within IE or Firefox.
Inspyder OrFind is a powerful webserver cleanup and monitoring tool. If you've ever wanted to know which files on your webserver are actually used by your website, the answer is here. OrFind crawls your site looking for all included files (even those included through CSS), it then checks your FTP...
A modern web site page has a a complicated structure that is hard to reveal. Frequently, it is required to find all the pictures URLs, to extract all the links from the page or to see the attached CSS style sheet.