I remember there is (or was) a command involving rundll32 that calls Windows XP's 'Turn Off Computer' menu – the one that can also be invoked by going to Start Menu > Turn Off Computer.

Does anyone happen to know/remember what the command is?
P.S.: I'm not talking about the 'shutdown' command.
Final edit: Well, the closest command to get this result with rundll32 is the following:
rundll32 msgina.dll,ShellShutdownDialog
But note that you'll get the 'classic' menu/dialog instead of the modern, 'themed' version. You can get the latter using a VBScript one-liner posted by techie007 below.