Akeda Bagus

The profile appearance mimics the profile page in GitHub. You just simply enter GitHub username and theme for the widget to show off the GitHub profile in a widget.
This plugin depends on <a href="https://wordpress.org/plugins/github-api/" rel="ugc">GitHub API</a> plugin. Make sure to install and activate that first.
Development of this plugin is done on <a href="https://github.com/gedex/wp-gh-profile-widget" rel="nofollow ugc">GitHub</a>. Pull requests are always welcome.

GitHub Profile Widget

Plugin extension for GitHub API plugin for showing off GitHub profile in a widget.

Claudio Sanches

This plugin adds Github Gists in your posts via shortcode.
Examples
Add a full gist:
<pre><code>[gist id="3837669"]
</code></pre>
Add a specific file in a gist:
<pre><code>[gist id="3837669" file="index.php"]
</code></pre>
<h3>License</h3>
Gist GitHub Shortcode is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published 
by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Gist GitHub Shortcode is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Gist GitHub Shortcode. If not, see <a href="http://www.gnu.org/licenses/" rel="nofollow ugc">http://www.gnu.org/licenses/</a>.

Gist GitHub Shortcode

Adds Github Gists in your posts via shortcode

GitHub Profile Widget vs Gist GitHub Shortcode