Laptops, Headless Servers and KVMs?

Administration of headless machines can be a pain, and working on multiple machines can also be a bit of a bother. KVM boxes solve some of the problem, but sometimes finding a keyboard and a monitor to lug around to these machines is most of the problem. Is there a portable solution that might solve both of these problems? Wouldn't it be nice to carry around a specialized laptop that could act as both a portable display and input device? Does something like this currently exist? KJH1138 asks: "I am looking for a hardware/software combination that would allow me to use my laptop as the KVM for a headless server before, during, and after OS configuration. What I have in mind would be a server KVM/USB to laptop serial/USB connection, with software on the laptop to provide KVM control of the headless device, with or without an OS. A PC Anywhere or Linux equivalent wouldn't work since they would require the headless system to already have an installed OS. I would prefer a Linux-based solution on the laptop, but would settle for a Windows option. I simply don't want the clutter of a keyboard and monitor."

PGillingwater has a similar desire: "Like many regular readers, sometimes I need to visit a customer site to diagnose equipment, like firewalls or routers. More systems these days use VGA output and keyboard input, which means having to scrounge a display and keyboard, then looking for a spare power socket in the machine room, which is not always easy! I am wondering if anyone has seen a laptop which also allows VGA input and keyboard output. This would be a cool idea. Use it as a normal laptop most of the time, then hijack the video and keyboard to connect to other systems when you need it."