If you have a wordpress installation in you own webspace, you may want to automatically publish your blog posting on twitter. You can do this with the Twitter Tools for WordPress.
Twitter Tools is a plugin that creates a complete integration between your WordPress blog and your Twitter account.
Notes about the installation and the configuration can be found on the plugin homepage.
Something which is not mentioned: You have to have the php curl library installed to use the plugin. The library was easily installed on my debian root server.
aptitude install php5-curl