Clicky Gone - Clicky Gone allows you to hide your selected windows from view, this includes the taskbar button...
RBTray - Allows almost any program to be minimized to the system tray by right clicking its minimize button.
mapmywindows - A small program to show and hide windows in X window system.
4t Tray Minimizer - 4t Tray Minimizer Free/Pro - Minimize Outlook, Internet Explorer, Firefox, Chrome and any other applications to the system tray!
TopMenu - TopMenu is a functionality clone of ...
Minime - Minime is a tool that allows you to minimize applications to the system tray using a simple hotkey.