With a bit of jquery, CSS and a SVG fallback, you will be able to create a cool blurring effect, that will focus your users on your sidebar.
Focus the user on some sidebar content, and blurring the useless content.
This way, the user can focus on your sidebar, and the blurred effect create a smooth & not-intrusive way to do it.
Of course, we want it to work everywhere, or almost everywhere ;) The effect can be applied to Firefox, Webkit browsers (Chrome, Safari, etc) and IE
If you liked the idea, and want to contribute, I will open a github repo dedicated to it soon, but you can fork it, modify it and/or use it as you want.