AA Github Profile Widget is a nice joomla module to show github profile in joomla
Extension info
The only required option is the user name of the Github user you want the widget to represent. You don't have to worry about capitalisation, as the plugin normalises the username.
Note: if you do not specify a username when running the plugin, it will list me instead, as I a set as the default.
Read more http://feeds.joomla.org/~r/JoomlaExtensions/~3/8WdOIw14KH8/aa-github-profile-widget