I never knew I really missed this feature – but now that I accidentally discovered it, I do now know how I should live without it!
OS X Leopard (10.5), and versions before that, display three colored bubbles in the top right corner of each window. Red to close it, green to maximize it, yellow to minimize it.
The yellow bubble did the following: click it and the window will disappear into the dock and sit right next to your stacks and the trash bin. Do that with multiple windows and you have – perfect chaos.
Now, with a single activated option in System Preferenes -> Dock, you can change this behaviour. If you click the yellow bubble now, the window will be minimized to the applications icon in the dock which prevents much clutter.
„Bullshit!“, you scream. „What if I have multiple windows for one application?“, you ask.
Calm down, young friend. Apple thought of that, too. Say, you have multiple windows of Safari open and you minimize them all to the icon in the dock. Now you want to re-open only one of your seven windows. You have two options to do that.
1) Right click the icon. The menu will pop up and above the known options (hide, quit, …) you’ll find a list of all your windows. Select the one you whish to open and you’re good to go.
2) Left click the icon and HOLD the mouse button a little. This will trigger a „light“ version of Exposé, that will only show you the windows belonging to that application.
Great, isn’t it?