Here is a list of free, open source blog software, applications, engines, blog wares and platforms which you can download and use for creating a blog, online diary or journal at your own domain and servers:
1) WordPress: WordPress is undoubtedly the best open source blogging platform. According to Forbes, it is used by more than 60 million sites and more than 100,000 users download it on a daily basis.
2) Drupal: Drupal is another incredible open source solution for creating weblogs. Apart from regular blogs you can create forums, mailing lists, chat, member profiles, and other great options which are specifically required for creating a community website in a fly.
3) Joomla: If you wish to create a blog with the look and features of a CMS then, Joomla is an excellent open source blogging software. It is a number one choice of many SMBs and SMEs for creating a website. Common community features includes: content management, user management, templates, polls, knowledge-base, etc.
4) Movable Type: By using Movable type you can create multiple sites and blogs in a single install. It is offered as free for individual bloggers but is paid for a
business site.
5) Expression Engine: Expression engine is a free blog software for personal, non commercial and non profit sites. If you wish to use it for a commercial site then you have to buy a paid version.
6) PHP Nuke: PHP NUke is an open source blog engine for creating a blog, news submission and integrated forum website.
7) Wheatblog: Wheatblog is a free blog creating software which can be used for creating a blog, and a new submission site.
8) FlatPress: FlatPress is a free blog software where you can create blogs without using a database.
9) LifeType: LifeType is a free blog application which creating blogs. Unique feature includes podcasting, bulk file uploads, multiple blogs, subdomains for users, and
allowing users to remotely create and edit blogs.
10) Blogcms: Blogcms is an open source blog software for creating blog, forum, feed aggregator, wiki and image gallery.
11) NucleusCMS: NucleusCMS is another free blog software. It has features of a common blog platform.
12) Dotclear: Dotclear is an open source blog software with media manager, translation ready and anti spam system.
13) Globber: Globber is a regular open source blogging software.
14) Habari: Habari is free blogware with integrated support for mobile themes.
15) Livestreet: Livestreet is an open source blog engine for creating blogs along with community features.
16) Loudblog: Loudblog is an open source blog platform especially for media content like podcasts, audio and video.
17) Serendipity: Serendipity is a free blog software which is fully localized and you can use it any type of database including SQLite, MySQL, MySQLi and PostgreSQL.
18) Pixie: Pixie is an open source blog platform with integrated sitemaps, spam protection, user management, etc.
19) glFusion: glFusion is a free blog application for creating blogs, forums, galleries, calendars and polls.
20) TextPattern: TextPattern is a free blog engine for easily creating a blog and community site.
21) B2evolution: B2evolution is an open source blog software with CMS and community features.
22) Nibbleblog: Nibbleblog is a free blog engine which is very easy to install.
23) SweetRice: SweetRice is an open source blog software and a website management system.
24) Croogo: Croogo is an open source blog platform built on CakePHP and MySQL.
25) Kukkaisvoima: Kukkaisvoima is a free blog engine which is built on Python.
26) Bricolagecms: Bricolagecms is an open source blog-ware built on Perl.
27) Boast Machine: Boast Machine is an open source blog software built on PHP and MySQL.
28) Oxite: Oxite is a free blog software which is built on ASP.NET.
29) Dasblog: Dasblog is an open source blog software built on ASP.NET 2.0 and C#. It doesn’t requires a database.
30) Mephisto: Mephisto is a free blog software which is built on Ruby on Rails.