GitHub Profile Fluency
This plugin adds a language display bar at the top of a user's profile. The display shows how many languages the user has used in their public repositories and has a color bar that mimics that of the repository language statistics bar.
Displays the number of languages that a user knows and the number of repositories that a user has.
If you click on the colored bar it will show the percentages of the languages that their repositories and forks are in.
This plugin has some flaws and doesn't display a 100% accurate representation of the languages that a user knows. However it is very fun to see what languages a user knows and for the most part is fairly reflective of the languages that the user prefers to write code in.