Both ArgumentNullException and ArgumentException have a constructor which takes two strings.  One is the name of the parameter (or argument) in question and the other is a string describing the exception.

The funny/odd/interesting thing about them is that one has the opposite order of arguments.

For ArgumentException the constructor is:

public ArgumentException(
    string message,
    string paramName
)

While for ArgumentNullException is it:

public ArgumentNullException(
    string paramName,
    string message
)

And my point is….

Well, I don’t have one I just thought it was an interesting thing to point out :)