ISAPI_Rewrite is a powerful URL manipulation engine based on regular expressions. It acts mostly like Apache’s mod_Rewrite, but is designed specifically for Microsoft’s Internet Information Server (IIS). ISAPI_Rewrite is an ISAPI filter written in pure C/C++ so it is extremely fast. ISAPI_Rewrite gives you the freedom to go beyond the standard URL schemes and develop your own scheme.
http://www.isapirewrite.com/
http://www.addedbytes.com/apache/url-rewriting-for-beginners/