Copitor is a 3ds Max script by Mathieu Jacquin which allows you to copy and paste selected objects to another 3ds Max scene or to another window if you have more then one 3ds Max open. It is also useful to back an object up before you try something, such as booleans!
You can download it here.
To install... Drop The file in max viewport and go to Customize ==> Customize User Interface ==> Category: zOffTy Tools ==> Copitor