Clicky Gone!

Allows almost any program to be minimized to the system tray by right clicking its minimize button.

FireTray is a Linux Mozilla addon that targets Mozilla Firefox, Thunderbird and SeaMonkey. It provides a system tray icon with much window handling functionality. For mail applications, the icon can show the number of unread or new messages. FireTray is very customizable.

4t Tray Minimizer is a lightweight but powerful window manager, which helps you to free up space on the desktop and the taskbar via the following actions:

SmartSystemMenu extends system menu of all windows in the system. It appends next custom items to menu:

PowerMenu is a small application that some extra menu items to the windows control menu in addition to the standard "Close", "Maximize", etc options. The extra menus are: Priority, Always On Top, Transparency and Minimize To Tray.

NuonSoft ShellEnhancer is a powerfull utility designed to enhance the default shell of Windows. Learn more about ShellEnhancer.

TopMenu is a functionality clone of PowerMenu, but designed to be compatible with Windows 7 and 64-bit systems.

TrayIt! - minimize to the system icon tray any program (Outlook Express, Notepad, Word, Internet Explorer, Sunbird, Thunderbird, Opera, OpenOffice etc.) and get more room in the Taskbar!

PS Tray Factory allows you to take a full control over icons in the system tray area of the taskbar. With PS Tray Factory you can: hide icons from system tray into menu, change the order of icons in the system tray (sort tray), restore tray icons after Explorer.exe crash and use custom icons.

AllTray is a program you can use on Unix-like systems such as GNU/Linux or FreeBSD running the X Window System to dock any application which doesn’t have a native tray icon into the system tray/notification area. AllTray works with many desktop environments and window managers, including Metacity on GNOME and KWin on KDE. The current release of AllTray is 0.7.2dev, and can be downloaded from Launchpad; the most recent stable release is 0.70 and is also available at that location

HideWin sits in the system tray and enables you to hide any top-level window with its popup tray menu or an ALT+letter hotkey that it assigns automatically. It appears to be abandonware, but it is only 13KB and still works.

Thunderbird-Tray is a system tray launcher tool for Mozilla Thunderbird.

KDocker will help you dock any application into the system tray. This means you can dock Openoffice, xmms, Firefox, Thunderbird, anything!

Process Manager for Windows is a utility which allows you to to set process priority, minimize windows to the system tray, and more—all via taskbar window button right-click menus.