RubLog is written in Ruby (www.ruby-lang.org), which has been a constant for me for the past two years. It supports CVS, categories, and multiple different file formats. Have a look here: www.pragprog.com/pragdave/Tech/Blog/SourceCode.rdoc,v.
One important thing to keep in mind is that, though my site is ugly, it’s always been ugly. You can’t blame this on RubLog’s creator (although if you think Dave’s site is ugly, you can blame that on him). :)
Now, I’m looking forward to the day when I can upload MS Word documents and have them appear as weblog entries. Not because I want to use Word, but because it’ll be cool.