How to import a video signal to a laptop?

Hi,
I’m looking for a way to use one of the many laptops I have floating around to work as a temporary display for a desktop computer. Why is this so hard to do?? Most computers only have Video->out functionality, but no import.

I am not editing video or anything like that, I just need a quick monitor and it would be a great solution to be able to carry a laptop over to where you need one and then export your display from the box or other laptop (trouble-shooting) that requires one.

I thought for sure there’d be a USB style device that would do this maybe with some software to load on the system or maybe even a PCMCIA card with a video out that I could buy just for the laptops, but I’m not see anything available- what gives?

Does anyone know of a way I can export a video signal to a laptop display?

The simplest solution might actually be network-based; programs like MaxiVista can turn your laptop into a virtual monitor that connects to your desktop over the Internet, ethernet, or local Wi-Fi. No additional hardware required. There might be some lag so this probably isn’t the ideal solution for gaming, etc., but it might just work for everyday office tasks.

You can also use the built in Remote desktop app if they are windows system.