No Machine hacks
No Machine produce an X11 proxy which achieves excellent compression and allows usable X11 forwarding even over a DSL link. The core protocol is open sourced and No Machine also sell server software that enables Citrix-like functionality on Linux and Solaris systems. In addition they offer a free download of a limited version of the software which allows up to two concurrent connections.
The tricks listed below will work on both the free and commercial versions.
Wrapper: Wrapper script to run arbitrary X11 sessions
RDP: Connect to a Terminal Services server behind a firewall
Floating window: All about floating window sessions
SeamlessRDP: Floating Terminal Services windows