Teleport for Mac

From Abyssoft:

Teleport is a simple utility to let you use one single mouse and keyboard to control several of your Macs. Simply reach the edge of your screen, and your mouse teleports to your other Mac. The pasteboard can even be synchronized between the computers. Using the convenient Preferences Pane, you configure which hosts you want to control, arrange them graphically like in the Monitors panel, and you're ready! Simply reach an edge of the screen where a slave host is connected, and you take control of the other Mac. The keyboard is acting like if it was connected on the controlled host, and the pasteboard has optionally been synchronized. On the master computer, a nice notification indicates that it controls another Mac, and shows you the position of your mouse cursor. To take back control of your main Mac, simply drag the mouse back from where your cursor came, just like when you have several monitors.