The initial idea and sources of this mod are originally from UltraMoogleMan.
CCTV means "closed-circuit television"
Right click on a screen to change channel
Here are the files (requires ModLoader Beta 1.7.3 ):
Download CCTV 2.2 for Minecraft 1.7.3
Simply put the .zip file in your ".minecraft\mods" directory after installing Modloader.
Here are the source files for those who would like to improve it:
Source code CCTV 0.1 MC 1.6.6