Using laptop as a second programming monitor
Synergy doesn't allow you to move windows between machines (that would require a silly amount of work behind the scenes), but it does allow you to share a keyboard and mouse between two machines so they "appear" to be all one machine, but actually run separately.
I personally use Input Director, as I found it more stable than Synergy. I have my laptop with an external monitor to the right, and my desktop to the left as an Input Director slave. My desktop runs a different O/S and is basically my guinea pig box for testing stuff and for anything I need to keep running when I leave the office. Cut + paste is pretty seamless, so I can quite happily fire up an RDP session to a server on my desktop, and cut+paste SQL scripts from that to my laptop.
It's a very useful thing to have if you have a few physical boxes and monitors kicking around :)
I've actually managed to use spare notebook as a second monitor to Desktop PC. This allows to move windows to second PC, but not vise-versa.
Solution would work basically with any OS.
The only requirement is a spare VGA (or DVI-I/DVI-A) port on server PC.
- Make a dummy VGA plug http://www.overclock.net/t/384733/the-30-second-dummy-plug This will also work for DVI-I/DVI-A port + DVI-VGA adapter
- Detect virtual monitor with your OS. Monitor will be detected as very generic monitor, so you can set up any resolution. Set it to slave PC resolution.
- Use any remote control software to connect from slave to server PC. Set it to display only "virtual" monitor.
That's all. Your slave PC is a second monitor for server PC.
I've used this on Windows 7 + TeamViewer. I've additionally set up Mouse Without Borders (Microsoft Synergy analog) to be able to use slave PC with same mouse&keyboard, though this is not required if you intend to transform it to monitor-only.
Xdmx - Distributed Multihead X Project (linux only)
Provides native X display on external machines, no VNC cons.