Worth a look --
nomachine.com From their website:
NoMachine NX is a Desktop Virtualization and Remote Access solution based on a comprehensive set of enterprise class open source technologies. Thanks to the outstanding compression, session resilience and resource management developed on top of the X-Window system, and the integration with the powerful audio, printing and resource sharing capabilities of the Unix world, NoMachine NX makes it possible to run any graphical application on any operating system across any network connection as if you were sitting in front of your computer.
NX Free Edition ** A complete solution for remote access to your Unix workstation. It allows 2 concurrent users to connect no matter what their location is, and share the desktop. NX Free Edition is incredibly easy to install and run, leverages the competence and quality of the company that makes NX and, most importantly, is free forever.
Using a compressed version of the X protocol, 2X TerminalServer for Linux provides users with a secure, personal Linux desktop accessible from anywhere in the world, over any connection...
2X TerminalServer for Linux is an Open Source project, licensed under the GPL and is free of charge. Only user to user support is available via the 2X forums.