Windows – Application to group windows together

Is there an application that will group arbitrary windows into a single window (in MS Windows). For example, I'd like to have two notepads in a single window side by side or a notepad and a HTML preview of the file I'm editing side by side.

I'd like to be able to alt-tab to that group of windows rather than have to alt-tab twice to get the on screen at one.

I'd like something like an IDE environment where I can have arbitrary applications as the panels, such as a VIM panel, a powershell console in another panel etc. ConEmu is able to load simple windows into a tab, I'm looking for something similar which has more layout options.

Is there anything like this?

Also, there are proper tiling managers, but I don't want to tile all my open applications.