Can I use fluxbox or parts of it with XGL/Compiz/Beryl?
No, you can’t. Fluxbox is a windowmanager, compiz and beryl are window managers (combined with a composite manager). So you can only replace fluxbox with one of them. KDE, GNOME and XFCE are desktop environments, which bring a windowmanager (kwin, metacity and xfwm) along. That’s why you can use them with compiz, only the windowmanager is replaced. Fluxbox is not modular, so you can’t use the fluxbox menu, toolbar, slit or anything else with compiz. You can read the eyecandy section for some nice effects with fluxbox or switch completely to compiz/beryl and miss all the great features fluxbox has.
