Try some of these additions to your wiki. Most are VERY easy to use and will dress it up and add functionality! Polls, Surveys, Videos, Tutorials, chats, forums and audio files...

http://educators.pbworks.com/Plugin

 Web Widgets--- A web widget is a portable chunk of code that can be installed and executed within any separate HTML-based web page by an end user without requiring additional compilation.

Google Gadgets for your Webpage  

 Create your own Google Font

Cooltext.com Design custom logos.

Make a realistic looking Newspaper Clipping.

Spell with Flickr:  Spell a word using images from Flickr

Free Hit Counter: Tiny Counter 

Add snapshots to your webpage.. http://www.snap.com/

Large group of icons to add to webpages, wikis, blogs, presentations.... etc.

http://commons.wikimedia.org/wiki/Crystal_Clear

Free images... http://www.masternewmedia.org/where_to_find_free_images_and_visuals/