This would be a nice feature to add to mIRC which should be turned off be default for the (many) users that probably like it that way it is. The nick list and tree view auto hide when not in focus of the cursor but are restored when the cursor rolls where ever these items are positioned and collapsed at. An example is firefox when in fullscreen mode, the address bar appears when you position the cursor at the top of the screen but goes away when the cursor leaves and when focus is lost.