From what I recall, someone (I think it was Khaled) said the reason mIRC won't display tabs in the chat area is because people could use it for flooding. But personally, to me, thats not a good reason at all. I visit many coding channels and tabs are very common in code. When you see the "box" show up instead of a tab it makes things very hard to read. If people are really concerned that a tab will cause a flood, then make it an option "interpret a tab as N spaces"