Simple comment system that you can host yourself using PHP and MySql.
Simply add something like the following 2 lines to any static html page.
<div id="comments"></div>
<script type="text/javascript" src="http://silentorbit.com/comments/inc/1/script.js"><script>
To also support when javascript is disabled use add the following code:
<noscript>
<object data="http://silentorbit.com/comments/inc/1/ref.html" width="600" height="500" />
</noscript>
For this to work you must have registered your site and be given a site id(sid) as seen being used in the code. This makes it possible for you as the site owner to allow anonymous comments and delete comments of others.
Source code is available at GitHub
Is available at http://silentorbit.com/comments/