Bargain Priced "Media Wall"

I am posting this in Home Theatre in the hopes some of you are familiar with the latest cable TV inputs, outputs, and audio and video switching devices.

In other threads, we have discussed using high end audio on the desktop with mini monitors in a nearfield configuration, and multiple video monitors.

This is all a lot of fun and highly recommended for when you must be working or in front of your computer.

Now, I am trying to build a "media wall" to the side of my desk where I can monitor 6 cable TV channels simultaneously, but then move the selected channel to a bigger screen while monitoring the audio.

Could anyone please suggest the simplest and easiest way to do this?

The idea would be to silently monitor say, 6 stations, but when something of interest appears, switch the audio on to monitor the sound through the audio monitors on the desktop.

Given that I am monitoring the audio remotely and not on the display devices, could I just use relatively inexpensive PC video monitors and HDMI inputs? I suppose I need to start with 6 cable boxes?

I have seen some pretty slick video switching devices, but they get very $$$.

So thanks for any reasonably priced ideas or solutions.