I want to create a windows utility application, which can be called anytime from within any other application using a keyboard shortcut, e.g.:
• Win + T<
An option for doing that programatically when your application start is calling this Windows API:
RegisterHotKey(IntPtr hwnd, int id, int fsModifiers, int vk);
And to unregister call this API:
UnregisterHotKey(IntPtr hwnd, int id);
Both exist in user32 APIs
http://www.pinvoke.net/search.aspx?search=RegisterHotKey&namespace=[All]