Is it is possible, with [Windows Forms](http://en.wikipedia.org/wiki/Windows_Forms) in .NET, to change the opacity of a form without it automatically changing the opacity of the controls within the form?

I have a form that is running maximized, that contains a flowlayoutpanel in the centre of the form with controls inside it. I would like to lower the opacity of the form so that the "spare" part around the flowlayoutpanel is partly transparent, but the flowlayoutpanel itself remains solid (im aiming for a [lightbox](http://www.huddletogether.com/projects/lightbox/) style effect).