This is a great trick you can play on your friends. To disable the display of local or networked drives when you click My Computer.
1. Go to Start -> Run.
2. Type regedit
3. Now go to: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
4. Now in the right pane, create a new DWORD item and name it NoDrives (it is case sensitive).
5. Now modify it's value and set it to 3FFFFFF (Hexadecimal) .
6. Now restart your computer.
7. So, now when you click on My Computer, no drives will be shown(all gone...).
To enable display of drives in My Computer, simply delete this DWORD item that you created. Again restart your computer. You can now see all the drives again. Magic.......