[xmonad] Minimise windows?

[Magnus Therning]

Is there a way of minimising windows in Xmonad?

I've found several times that I really miss minimising of windows.
Right now e.g. I have a screen with VirtualBox (its control window and
a window for a single VM) and I want to stick a browser next to the VM
to follow some instructions on a web page.  What I've ended up doing
so far is moving the control window to a "scratch screen" so that the
screen is divided evenly between the VM and the browser.  However,
once I'm done I'll move the browser back to the "web screen" and I'll
have to move the control window back again from the "scratch screen".

Are others bumping into this use case?  How are you dealing with it?

/M