This addon would allow you to communicate in any major city general chat. It would simply join the specified major city channels and provide the chat in it's own "CellularChat" chatbox. Great when Looking for Groups, or Looking for Additional party Members while allowing you to continue farming, or questing in the process.
The reason this would require an addon is simple. There are certain situations in which creating sucha a chatbox ourselves would create unnecessary dilenmas. In certain situations if you were to be communicating in a Major city's general chat as soon as you were to enter into that city it would bug your general chat. Making it extremely rough to communicate in general at all. Usually ending in the deletion of your chat settings file.
This addon would have to efficiently remove you from a Major City's general chat anytime you are about to enter that city. How this would happen I am uncertain. Maybe something similar to an onevent when someone leaves or joins a channel.. Like a coded version of this:
OnEvent_Leave generalchannel LeaveAllCellularChatchannels
if Generalchannel = General - Orgrimmar
then JoinCellular Chatchannel General - Undercity and JoinCellular Chatchannel General - ThunderBluff
Elseif Generalchannel = General - Undercity
then JoinCellular Chatchannel General - Orgrimmar and JoinCellular Chatchannel General - ThunderBluff
Elseif Generalchannel = General - ThunderBluff
then JoinCellular Chatchannel General - Orgrimmar and JoinCellular Chatchannel General - Undercity
In addition to this bug solution, there would also have to be some way to minimize, or hide this CellularChat Chatbox when not in use. Either by using a minimize button, or binding a key to allow for this.