If you will install XBMC, Boxee or do something else on your Apple Tv, you need a way to access your ATV. This article will show you how easy you can access a Apple Tv through a ftp client.
1. Download Cyberduck. It's a Open source FTP client. http://cyberduck.ch/
2. Unzip and install Cyberduck on Mac or Windows.
3. Open Cyberduck and click on "Open connection"
4. Select SFTP (SSH File Transfer Protocol)
5. Under Server, use your Apple tv's IP adress. Something like "192.168.1.100"
6. Default Username is root
7. Default Password is alpine
Now you are connected.