This would add a command to turn individual channels off at a time, if you turned all off at one time you could only receive chat through pm's, this would help stay focused on different channels/pm's. Might come in handy to supporter's, (my friend was complaining about supporter's chat, and having no way to avoid it completely)
Or you could do /ch pm and it would only let you see PM's? I would like that, so I can have the peace and quiet of having the chat off, but still being able to see PM's that people send me so I know if I need to turn chat back on. I like your thinking, zombie.
We had this before the new chat update - it was removed because it caused quite a lot of lag due to the system having to track which messages were from where.