Knowing where you are in the SERP's (search engine result pages) will aid you in improving your site's position with the search engines. This tool allows you to monitor many aspects of your site with regards to the search engines. Just look at what it can show you:

• Check your index position on Google, MSN and Yahoo
• Check your page rank with Google
• Check your link popularity
• Check your keyword density
• Check for broken links
• Check for a sites proper return code
• Check for links with session ID's in search engine listings
• Check for links that are in googles supplemental index