Window Hide Tool 

Window Hide Tool will help you to quickly hide a window of any application. You can set hotkeys for basic program commands: hide a window; hide all windows; hide a group of windows.
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4t Tray Minimizer Free 

4t Tray Minimizer lets you running applications minimized as System Tray icons. The System tray icons can be hidden to let you easily read the buttons on your taskbar. Also you can customize the favorites with special hidding behavior and launch key.
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Simple System Tray IMAP Client 

This program includes a few interesting and useful technologies i.e. - A Simple System Tray IMAP Mail Client (not available so far) - System Tray Implementation in Visual C#.Net
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AceHide 

It is possible to hide any application windows by using a hotkey or via an icon in your system tray.
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