This is a very simple plugin that shows a cloud of the most frequently used words in your wiki:

~~CLOUD~~
~~CLOUD:number~~

Optionally you can specify the number of words to display. Default is 50. Allowed are numbers between 1 and 999. Each of the words is linked to the search result page for it. The words are styled in a way that more frequent words are bigger and have a darker link color.

You can exclude words from the word cloud by adding them each on its own line to inc/lang/[lang-code]/stopwords.txt or to conf/stopwords.txt.

This plugin can also make a “tag cloud” now! (Tags plugin must be installed) The syntax is also simple:

~~TAGCLOUD~~

For more information, please also see the author's site. http://www.wikidesign.ch/en/plugin/cloud/start