When you use Synergy, it connects one computer (and desktop) to another. Your mouse will flow seamlessly from one desktop to the next. A number of desktops can be combined, although programs remain confined to their desktops.
Synergy is different from multiscreen desktops – a standard multiscreen desktop stretches a single operating system environment across multiple screens or displays. In most normal cases, this is what would be preferred for normal users. However, if you are using multiple systems for different purposes, you can concatenate separate displays together.
When you move your mouse from one desktop (Mac OS X, for instance) to another, it is like moving from one computer to the next. In some ways, it is like a multi-screen software KVM (Keyboard-Video-Mouse) switch. The server runs on the system with the keyboard and mouse, and the clients run on other systems. Each system has its own monitor, and can be placed (virtually) anywhere through proper configuration of the server. For example, the screens could be placed one on top of the other, or side by side. If one display is disconnected, then it will be skipped. For example, if there are three screens in a row, and the middle one loses connection to the server, then it will be skipped over as the mouse moves from one system to the other.
Recently, I had the server running on Mac OS X, a client on Fedora Core 5, and a client under Solaris 8. The mouse could then be moved to the left side of the Mac OS X display, and it would appear on the right on the Fedora Core 5 display. Continuing to move the mouse, it would eventually wind up on the Solaris 8 display. The only drawbacks are the network delay and differing mouse speeds. I’ve grown addicted to it – try it today!