Free SEO Toolkit From Microsoft

Search Engine Optimization (SEO) Toolkit is a free tool from Microsoft for improving a website’s relevance in search results.
It simply analyzes a website & recommends how to make your new or existing site content/structure more search engine-friendly.

Some features of SEO Toolkit:

• full-featured crawler engine
• query builder interface that allows you to build custom reports
• display of detailed information for each UR
• ability to manage robots.txt file
• ability to manage sitemap.xml file

It requires an IIS7 enabled computer to run which is basically Vista, Windows 7 or Server 2008. After that it can analyze any local or remote website.
P.S. Besides standard installation, SEO Toolkit can be installed easily using the Microsoft Web Platform.