Hey joe I improved my function:

      $x=function() {
      	for (var i=0;i<arguments.length;i++) {
      		switch(typeof arguments[i]) {
      			case "string":var x=arguments[i];break;
      			case "number":var type=arguments[i];break;
      			case "object":var node=arguments[i];break;
      		}
      	}
      	return (!type) ? document.evaluate(x,(!node?document:node),null,9,null).singleNodeValue : document.evaluate(x,(!node?document:node),null,type,null)
      };
      

It's overloaded and accepts arguments on type, not order. So $x(".//text()", document.links[0]) or $x(document.links[0],".//text()") would work.

Tell me if it works / needs more features please.

Assumptions:

1. That if the Result Type isn't supplied, you want to get the first result.
2. That if the Node isn't supplied, it will be checked against the document.

Joe, I made an overloaded XPath function, wanted to share it with you. Here it is:

      $x=function(x,type) {
      	return (!type) ? document.evaluate(x,document,null,9,null).singleNodeValue : document.evaluate(x,document,null,type,null)
      };
      

So if you want only the first result, don't supply the second part:

$x("//div[@class='header']")

or if you want all the results, just specify the type:

$x("//div[@id='footer']//a",7)

Yeah, instead of writing a greasemonkey script, you should just write the CSS for Stylish, then post it up on UserStyles.

You should take a look at Stylish. ;)

Seems nice! Thanks!