shelkie

Manage multiple blogs with a single standard WordPress installation. Each may have its own theme and domain while sharing users and administration.
Handy for situations where multiple blogs or domains are required, but WordPress MU seems like overkill. MiniMU adds this functionality without added complexity or administration headaches.
By associating a WordPress category with each of your domains, you’re able to control where your posts and pages appear. Have some posts and pages show up on a single domain, and others be visible on all domains. Simply assign the appropriate categories to your posts and pages to control where they appear.
You are able to select a different theme for each MiniMU domain if so desired. Additionally, you’re able to change the Blog title and Tagline for each. Often, it’s desirable to include other bits of content that vary by domain. MiniMU allows you to create custom “variables”, and assign unique content for each domain. These bits of custom content may be plain text or HTML.

MiniMU

Manage multiple blogs with a single standard WordPress installation. Each may have its own theme and domain while sharing users and administration.

krazykoder

Freedom Permalinks can help you to change permalinks to any format you want. 
Update slug structure, change domains, remove/add slashes or add extensions (.html, .php or anything you want) etc.
<pre><code>PS. While this gives you freedom to play with permalinks, you should know that you have to make those link structures work with your themes yourself.
</code></pre>
For example if your theme is installed on subdomain1.domain.com, changing permalink to subdomain2.domain.com will break the existing links and you have to move your theme manually to subdomain2.domain.com to make it work.
<pre><code>Things you must know before trying this plugin:
1. It's best suited for custom/smaller themes.
2. Always create backup of your database before trying this plugin.

Examples:
Some permalink examples to just give you some idea to what we can do with "Freedom Permalinks".
Permalink : http://subdomain-anydomain2.com/blog/%post_id%/%post_slug%
Becomes : http://subdomain-anydomain2.com/blog/23/this-is-smaple-page-post

Permalink : http://subdomain.com/blog/%post_id%/%post_slug%.html
Becomes : http://subdomain.com/blog/23/this-is-smaple-page-post.html

Permalink : http://subdomain.com/blog/%post_slug%.html
Becomes : http://subdomain.com/blog/this-is-smaple-page-post.html

Permalink : http://subdomain.com/blog/%post_category%/%post_slug%.html
Becomes : http://subdomain.com/blog/health/this-is-smaple-page-post.html

Permalink : http://nes.subdomain.com/news/%post_category%/%post_slug%-%post_id%
Becomes : http://nes.subdomain.com/news/mobile/some-ceo-retired-23
</code></pre>

Freedom Permalinks

Change permalinks for standard or custom post types while using any domain name you want.

MiniMU vs Freedom Permalinks