http://www.alexa.com/siteinfo/besthostingforums.com
The rank is calculated using a combination of average daily visitors to
besthostingforums.com and pageviews on besthostingforums.com over the past 3 months. The site with the highest combination of visitors and pageviews is ranked #1.
That's why the regex fails.
Here's a fix:
PHP Code: 
function GetAlexaTrafficRank($domain)
{
        
$source file_get_contents("http://www.alexa.com/siteinfo/$domain#");
        
$regex '#([0-9,]+)\s*</div>\s*<div class="label">Global Rank#';
        
preg_match($regex$source$match);
        
$newresult str_replace("number"""$match[1]);
        return 
$newresult;
}
echo 
"KWWHunction's Alexa Traffic Rank is: ".GetAlexaTrafficRank("besthostingforums.com")."."
deliteblogger Reviewed by deliteblogger on . [PHP] GetAlexaTrafficRank GetAlexaTrafficRank Pass through a domain without 'www' in "$domain". Read, Learn, Modify, Re-use. Example output: http://screensnapr.com/e/uOxR3O.jpg Code: <?php Rating: 5