Accessible Search is an early Google Labs product designed to identify and prioritize search results that are more easily usable by blind and visually impaired users. Regular Google search helps you find a set of documents that is most relevant to your tasks. Accessible Search goes one step further by helping you find the most accessible pages in that result set.
Google Accessible Search is designed to help the visually challenged find the most relevant, useful and comprehensive information, as quickly as possible.
In the past, visually impaired Google users have often waded through a lot of inaccessible websites and pages to find the required information. "Our goal is to provide a more useful and accessible web search experience for the blind and visually impaired".
Google defines accessible websites and pages as content that the blind and visually challenged can use and consume using standard online technology, and they've worked with a number of organizations to determine which websites and pages meet those criteria. The search takes into account several factors, including a given page's simplicity, how much visual imagery it carries and whether or not it's primary purpose is immediately viable with keyboard navigation.
Click this link to visit the Google Accessible Search website: http://labs.google.com/accessible/.