As a part of his work being done on the WinPHP Challenge, Rob Allen has done some work with routing and Microsoft's IIS7 web server.
I've already covered the Sqlsrv adapter, so let's look at rewriting requests with IIS7's URL Rewrite module. As with everything in IIS, you get at this tool via the IIS Manager GUI. Be aware though that the Url Rewrite icon is available at server level and at the website level.
The module allows you to define rules similar to mod_rewrite with Apache and even lets you import them from a current installation. The "Import Rules" panel lets you either specify a configuration file to pull from or lets you cut and paste the rules in for import (as seen here).