Throwing custom exceptions in Javascript. Which style to use?

Douglas Crockford recommends doing something like this:

throw {
    name: "System Error",
    message: "Something horrible happened."
};

But you could also do something like this:

function IllegalArgumentException(message) {
    this.message = message;
}

throw new IllegalArgumentException("Argument cannot be less than zero");

and then do:

try {
    //some code that generates exceptions
} catch(e) {    
    if(e instanceof IllegalArgumentException) {
        //handle this
    } else if(e instanceof SomeOtherTypeOfException) {
        //handle this
    }
}

I guess you could include a type property in Crockford's implementation and then examine that instead of doing an instanceof. Is there any advantage from doing one versus the other?

Update 2022

If your environment supports ES6, you should use inheritance from Error class, as recommended by Mozilla:

class IllegalArgumentException extends Error {
   // ...
}

This is also the most upvoted answer in What's a good way to extend Error in JavaScript?.

Pre-ES6 (original answer)

Also pre-ES6 environments provide the Error class as basis for exceptions. It already allows you to define a message, but also provides a useful stack property to track down the context of the exception. You can create your own exception type by using prototypical inheritance. There are already several stackoverflow discussions (for example: here), how to do this properly. However, I had to dig a little bit until I found the correct and modern approach. Please be aware that the approach that is suggested in the Mozilla documentation (see above) is not liked by the stackoverflow community. After a lot of reading I came out with that approach for inherit from Error.prototype:

function IllegalArgumentException(sMessage) {
    this.name = "IllegalArgumentException";
    this.message = sMessage;
    this.stack = (new Error()).stack;
}
IllegalArgumentException.prototype = Object.create(Error.prototype);
IllegalArgumentException.prototype.constructor = IllegalArgumentException;