The Code

Save the following user script as yahooprefetch.user.js:

	// ==UserScript==
	// @name Yahoo! Prefetcher
	// @namespace http://www.oreilly.com/catalog/greasemonkeyhks/
	// @description prefetch first link on Yahoo! web search results
	// @include http://search.yahoo.com/search*
	// ==/UserScript==

	var elmFirstResult = document.evaluate("//a[@class='yschttl']", document,
        null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue; 
	if (!elmFirstResult) return; 
	var urlFirstResult = unescape(elmFirstResult.href.replace(/^.*\*-/, '')); 
	var oRequest = {
        method: 'GET',
		url: urlFirstResult,
		headers: {'X-Moz': 'prefetch',
              'Referer': location.href}};
        GM_log('prefetching ' + urlFirstResult);
		GM_xmlhttpRequest(oRequest);