After poking around a bit, I settled on DokuWiki to set up a small experimental site. All the good things that I heard about it seems to be true. Setting up is totally painless and fast, it took less than 10 minutes from downloading the source code to having the first page up. The syntax is pretty straight forward, although I'd prefer the default rule for header levels to be reversed (without installing plug-ins). Customizing the appearance, either by tweaking the templates myself or installing custom themes, is also easy enough, but because I like the default ones, I don't plan to change that yet.
Guess now the really challenge is to put enough useful things there. Right now I only have some random notes on the site, serving as memos for myself. Hopefully I'll have the time to organize my major bioinfo protocols there soon.