It can be done with varying degrees of difficulty. If both machines are on a corporate network or connected via VPN, you could use something like RealVNC. With RealVNC no one needs to be at the remote computer because you can run a server that accepts connection but you need to be able to ping the machine remotely. I assume that this is not the case and the two machines are on local non-routable networks with firewalls that will prevent internet access.
In this case you’ll need to use a server that is on the internet for both machines to see. Do a Google search on “remote desktop” and you’ll get hits for sites like GoToMyPC.com, Webex.com, etc. that offer desktop sharing of remote computers.
~jr
http://www.johnrofrano.com
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