RealVNC - (Free)
Viewing and even controlling one remote computer from another desktop computer is possible with RealVNC which also offer the possibility to do this with computer with different platforms.
RealVNC is a VNC (Virtual Network Computing) customer developed to take control of remote computers, provided that VNC server is running on the remote machines.
User can view and use the remote server with a simple client program from any other computer in the world. One of the main advantages of Real VNC is that computers can have different platforms being possible, for example, to view and control a workstation running Linux from the personal computer with Windows.