Quick Tip - A Shortcut for Closing Active Drawing

You already know that ALT+F4 can effectively be used to quit a running application in windows operating system. For those who don't know, pressing CTRL+F4 inside AutoCAD will close the active drawing without touching the application or other drawings already open over there. Though it's a more straight forward shortcut than the ALT+F+C, I would like to stick to the latter as it looks easier to me (May be because I am used to that). CTRL+F4 shortcut is not limited to AutoCAD, but it works well with almost all windows multi document interface (MDI) applications.