I have a softmodded Xbox running UnleashX as the dashboard and I have XBMC installed as well. Is it possible to access the Xbox from my PC (not FTPing files) and control the Xbox with my PC, kind of like a remote desktop? If it's possible, any help will be appreciated. Thanks in advance.

http://xbmc.org/wiki/?title=The_Web_Interface ?

Or xbox neighborhood with xdk installed.

Install XDSL on your xbox then install RealVNC client on it. Install RealVNC viewer on your PC. Run RealVNCclient on xbox, and run RealVNC viewer on PC. Put in your xbox IP and voila!