Yes there is but it can be kinda complicated if you're not used to using a config editor. If you install Ubuntu Tweak for instance, you'll be able to set various title bar actions up as you like.
But I hear what you really asking... its a great idea!
But the problem with that is that it may conflict when an app has more than one window open. Say firefox and an associated download dialog window... one can click the firefox launcher icon and see those two windows.
What it sounds like you're asking for is IF there is only one window open (like say you started the calculator) why not when you select the calc launcher icon, it minimizes instead of doing nothing. And IF there happened to be more than one window open then default as it currently does to display those windows.
Are we talking the same thing...?
Why can't I use the Unity launcher icon to minimize applications/windows?