I could have sworn that I had actually made one... but can I find it? Nope, not even a sniff of it
You need XP Pro, Tablet PC Edition or MCE.
Control Panel > System > Remote > Allow users to remotely connect to this computer
If you want non administrators to be able to connect hit the 'select remote users' button and add them in
All you should now need to to is head to the H/PC - on a working network - and type in the network address of the XP system into the address box.