This is the best solution since it works fine in all my versions of perl, and it is very simple. Thanks! I'm curious why all solutions make the window "always on top" though.
In Tk, overrideredirect removes decorations and puts the window on top across all your virtual desktops with a global grab, it's not the best thing. In Gtk2, you can get more control, where you can remove decorations and set global_grab separately.