Kind of a crazy name for a piece of software (in this politically correct world, the use of "screw" doesn't go over very well with some management) but a really great example of Open Source in action.
I was hunting around for a wiki for our development documentation and standards. My first thought was SharePoint but we're not rolled out yet to 2007 and I didn't want to bank on that yet. I wasn't quite sure what I was looking for, but needed a wiki that did basic features and had a few "must-have" features (like AD integration and content approval). A great site for checking out and comparing wikis is WikiMatrix. This site lets you compare *all* of the wiki software packages out there and even includes a wizard to step you through what you're looking for (OSS, platform, history, etc.) and gives you a nice side-by-side comparison page (much like comparing cars) to help you select a package.
First I took a look at FlexWiki which was fairly popular and easy to setup. I had set it up on my laptop before as I was toying around with using a wiki as my home page. FlexWiki was simple and more importantly (for me anyways) it was C# and windows based so if I wanted to extend it, play around, write extensions, etc. then that would be bonus. Flex is nice and if you don't look at anything else, probably suites the purpose (although CSS-style customization seems to be pretty complex). While I was leaning towards C# type wikis, I knew that the best and most mature ones were PHP/MySQL based (like the one Wikipedia runs on, MediaWiki). However I just didn't want to introduce another stack of technology at my client just for the purpose of documentation.
Finally I stumbled across ScrewTurn Wiki. Like Flex, it was easy to setup and like my favorite blogging software (dasBlog) it could be file based so you could just set it up and go. I installed ScrewTurn and messed around with it and it worked well. We handed the duties of really digging into it over to a co-op student we have for the summer and he's really gone to town with it. AD integration was added (it was always there, I just didn't enable it) and he's found some plugins and even written some code to extend it. What's very cool about ScrewTurn is that the common pages are written in C# and live as .cs files on your server. You just edit them and override methods, introduce new ones, whatever. New functionality without having to recompile assemblies or anything (everything is just JIT'd on the fly).
Anyways, ScrewTurn looks like a very good IIS based wiki if that's your thing. I find it more mature than Flex, written in C# 2.0 and has a lot of great features. Like I said, if you have a LAMP environment in your world then you might want to look at something like MediaWiki but for a Microsoft world, ScrewTurn is da bomb. The plugin support is great and I'm hoping that the community will step up and build new plugins for the system so it can grow into something special.
So you might want to give ScrewTurn a try if you're looking for a simple documentation system for your team.