My latest favorite tool: Synergy. Synergy lets me control other computers with my primary computer’s mouse and keyboard. So it’s like having a multi-monitor setup across computers or like having a software KVM that works over the network. In the setup below, the laptop in the middle is my primary computer and with Synergy, I can drag my mouse cursor from my primary computer to the Dell laptop on the left and I can control the Dell using the mouse and keyboard on my primary computer. The setup could be easier, but once you have it installed, it just works. Another nice thing is that your clipboard is also copied across computers. So you could copy a string on one computer and paste it on another. The setup could be easier, but otherwise I highly recommend Synergy.