Blogical
http://github.com/cjheath/blogical
Blogical is a Sinatra-based micro-blogging engine that requires no database support.
It supports Markdown, and produces ATOM feeds from your metadata. It can run in various limited hosted environments, including free Heroku server and on DreamHost.
Blogical does not support comments, and is built for only a single author.
Copyright
Blogical is available under the MIT license.
Credits
Blogical is derived from Marcus Crafter's "jd" code.