WinSpy - Retrieve window information.
htop - htop - an interactive process viewer for Unix. This is htop, an interactive process viewer for Unix systems. It is a text-mode application (for console or X terminals) and requires ncurses. Latest release: htop 2.
Winspector Spy - Have you ever used Spy++ that comes with MSVC?
Microsoft Spy++ - Spy++ (SPYXX.EXE) is a Win32-based utility that gives you a graphical view of the system’s...
Process Explorer - The top window always shows a list of the currently active processes, including the names of their owning accounts, whereas the information displayed in the bottom window depends on the mode that Process Explorer is in: if it is in handle mode you'l…
XWinspector - Discover hidden features of other software with XWinSpector.