Many times I have wanted to move a tab into a new window in IE7, but have been frustrated that the tab remains in the old tab group when you press control-N. Install this Autohotkey executable in your Windows startup folder to make IE7 behave sensibly, so when you press control-N it moves the currently open tab to a new window.
Alternately, you can do this manually, by pressing “control down, n, w, control up,” or add the below Autohotkey code to your startup script to change the behavior of control-N so that it does not duplicate the current tab, but relocates it. Maybe someday Microsoft will fix this undesirable behavior. Firefox users, look here.
Control-N moves tab to new window in IE7
#IfWinActive ahk_class IEFrame