Lynx Viewer - Tool for seeing how a given web page is displayed when using a text-mode browser.
Search Engine Simulator - Tool that allows you to view a given web page and see how search engines or search engine spiders see a web page.
Standards for Robot Exclusion - Introduction to robots, with information on how to properly set encoding instructions in regards to accessing areas of your website.
Web Page Backward Compatibility Viewer - Tool to check the compatibility of several features on web pages when viewed using different browsers.