How to catch any key pressed in any other running applications?

[Bob]

I have a app which I want to popup by pressing some keys combination. Let's say how the tackmanager does it. Can not find any clue about it.

[Clay Burch]

One way to do this is to use the SetWindowsHookEx Win32 API. Check out the help on this Windows SDK call as well as this FAQ.

How can I use ’Hooks’ in .NET?
http://www.syncfusion.com/faq/winforms/search/618.asp