Thanks for that reply, @kenbuja. That's pretty much the same code I have, and it works beautifully.
Incidentally, I discovered that this technique can also be used with a System.Windows.Forms.MessageBox object. As you know (or will eventually find out), the default location for the MessageBox is at the CENTER OF YOUR DISPLAY SCREEN. This behavior is not what I prefer, so I use the Win32 Window Wrapper technique, as follows:
I hope someone finds this as useful as I have.
' Example 1: This will open a MessageBox at the center of YOUR FORM:
MessageBox.Show(New Win32HWNDWrapper(MyFormInstanceName.Handle), "This is the message", "This is the caption")
' Example 2: This will open a MessageBox at the center of the ARCMAP APPLICATION WINDOW:
MessageBox.Show(New Win32HWNDWrapper(My.ArcMap.Application.Hwnd), "This is the message", "This is the caption")