How can I host multiple websites in IIS 7 and use the same MVC application for all them?

How can I host multiple websites in IIS 7 and use the same MVC application for all of them such that each website:

1. Has it's own root directory so user's can upload their own files (html, css, javascript) without seeing other websites'content

2. Uses the same MVC application - so updates to the application affect all sites

3. Users cannot affect the MVC application in any way (preferably it will be hidden from them)

Thanks!