I was recently introduced to Oddmuse, a simple Wiki engine written in Perl. I initially set it up for a side software project I'm working on with friends (we needed a simple way to capture and share requirements and ideas). After that, I made www.pettijohn.com use it. One thing about it that appeals to me is that it's so easy to set up. Literally drop the script in, change one config value, and it works. You can tweak (which I've done), but there are no dependencies on databases or anything (it's filesystem-based). Nice job, Alex.