1. Strong keyboard shortcuts. As an emacs junkie as I am, I love keyboard shortcuts. And Fluxbox is incredibly flexible in defining or removing them: Even system-wide shortcuts are customizable. And avoiding the use of the trackpad (if it were as good as a Macbook one, I wouldn't mind, but it's not the case) is a big point. Now I have keyboard shortcuts, usually Windows key (I found something useful to do with it!) and a letter (i.e. WK+e for emacs, WK+f for Firefox) or Control+Windows key+letter, if it has already been defined (WK+p is Pidgin, and C+WK+p is gnome-screenshot).
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