In this tutorial on the LotsOfCode website, the author looks to help you create a feature common to several (including this one) websites out there - a tag cloud.

In this tutorial i am going to show you how to create a basic word / tag cloud using php. I am going to create a class based cloud, this is because it will be more convenient for people to adapt it on there own websites, if you don't know much about class based programming then click here to take a look at the class tutorial.

They pull the information from their "words array" (where words can be dynamically added to it) and use a percentage rating to base the CSS size for the data's span tag. The entire class listing is provided in one big chunk to make copy and paste easy.