WordCloud jQuery Plugin
So, first, I had to look at all the words and calculate their importance based on repetition in the list. Then, I had to update the list by removing duplicates and updating each tag with a number representing the reoccurrence of the tag in the list. Finally, I could run through most of the original tagcloud code (with a little cleanup) and update the size and colors accordingly. Check out the demo or download from GitHub. There is also a real example in this Online Instagram Viewer (look at the tag cloud after making a search).
While we are on the subject, html5snippets has a pretty cool design example for making CSS3 Tags and if you want to get really fancy, this d3 tag cloud example is pretty awesome. It actually makes me think of wordle and wordle in PHP.