I think PmWiki is a cut above the other wiki's out there in terms of the versatility of programs, the ease of editing the core, and the ability to skin the wiki.
Great Job, and keep up the good work!
I currently use:
- Sort by Score
To name a few.
And i absolutely love skinning my own wiki's (i start with a default for the general layout (I <3 Blix) but then take it from there).