Keep windows afloat (heh) on top of all others. Pin windows to the desktop. Move windows from anywhere, not just the title bar. Turn a window into an "overlay" on your screen that doesn't hinder your work. Show a window's file in the Finder with nothing more than your keyboard. Resize windows from anywhere, not just the edges, and more.
Hard to find free app that can make every app afloat, on windows it's free. Damn patent trolling! Maybe there's a torrent or something.