Simply put: It's a Zen thing...
Blosxonomy is a very lightweight Blosxom like blogging system written in Ruby, and designed around four core ities: simplic-ity, taggabil-ity, extensibil-ity and compatibil-ity.
Download the latest version, and a sample flavour to get started! There's also a set of plugins too. Already a pyBlosxom user?