MissingRemote has a great article on enabling Concurrent Sessions in Windows 7. Doing this allows you to access a system using one user account via remote desktop that is already being used by a different user account. This method lets you access the system without "kicking off" the original user. This could be used to run Media Center at the TV and "remote into" the main user account to access all files without interrupting the Media Center session.
Read the tutorials at Missing Remote: