You don't want to get the value each time a page is loaded. What you want to do is get the value every hour or every day or something like that, and save it to a database or file. The way I achieved this was to create a PHP script which extracts the ticker info from Mt. Gox and saves it to a file and/or into a database. Next I used Cron Jobs to make the script run automatically every two hours.
I will write a thread that describes how to do this (and provide the project code). BUT FIRST I need a little bit of help. My script was running smoothly until after the Mt. Gox crash. Now that Mt. Gox is back online my script still doesn't seem to be working. I checked the Mt. Gox ticker file manually and it seemed to be providing the json data as it should.
So that led me to believe maybe they were filtering out some of the headers. I was initially using the simple file_get_contents() function to retrieve the ticker data, so I decided to try the cURL functions and modify the header information to spoof my user agent. But that didn't seem to work either. Any help will be appreciated!
EDIT: Do not worry peoples, I have figured it out! I am writing up a thread on this now. I hope people will find it useful.
EDIT: Here you go: http://forum.bitcoin.org/index.php?topic=22886.0