Since I’m not using any window decorator for my gnome setup, I always count on keyboard and mouse combination shortcut for managing my windows. These are my regularly used shortcuts when I’m working.

• Alt + mouse button 1 (left mouse button): move window. Remember this, and your life would be lot easier. Seriously. I even bring this habbit to MS Windows. You don’t need to move your mouse to title bar and click it there to move the window. Just hold Alt button, and click anywhere inside the window, and you could move it anywhere.
• Ctrl + Alt + d: show desktop. Easily “minimize” all your opened windows. Very useful when your desktop is cluttered and you want to open new application.
• Alt + F9: minimize current window.
• Alt + F8: resize current window. Having no window decorator makes resizing window a little bid harder. But Alt + F8 really helps a lot.
• Alt + F7: move current window.
• Alt + F10: maximize current window.
• Alt + F5: unmaximize current window.
• Alt + F4: close window. Some application could also use Ctrl + W, Alt + Q.