How do you minimize a window in the Visual Studio 2010 RC editor?

I am using the Visual Studio 2010 RC. Sometimes when I am working on a code file, I would like to minimize it.

In Visual Studio 2008 I just switched to MDI mode. Then I could minimize. In 2010, I can undock the window by dragging the tab, and that gets me half way to MDI, but I see no way to minimize the window.

Does anyone know how to do this?

Update - Closely-related question: For those of you that used MDI, how are you getting by? I like to have 4 documents open at once开发者_开发知识库, in a 2x2 matrix. For example I like to look at one controller/view pair while working on another, for the sake of comparison. Then, maybe I edit my repository file, and I want to get back to my 4 windows. This is where I would minimize. Anyone have a workaround? How have you adapted?

Update 2 - Vote up my suggestion if you want this feature: https://connect.microsoft.com/VisualStudio/feedback/details/536110/please-offer-this-ultra-quick-alternative-to-a-minimize-feature-for-the-vs-2010-ide#

I think its disabled. I pressed Alt-Space in the undocked window and minimise was disabled.