Please list here ideas for potential plugins. Do not include lengthy discussion about why/how the plugin should work, but link instead to an issue where this would have been discussed.
By listing these ideas here, we can keep the issues list a bit more clean, and have a centralized place where people wanting to contribute can find potential enhancement ideas.
Also have a look at https://github.com/shaarli/Shaarli/issues/14 for other suggestions.

* [Mozilla Social API integration](https://github.com/shaarli/Shaarli/issues/101)
* [File sharing/Upload service integration](https://github.com/shaarli/Shaarli/issues/58)
* [Publish to social media services (twitter, facebook, ...)](https://github.com/sebsauvage/Shaarli/pull/70)
* [Comment system](https://github.com/sebsauvage/Shaarli/issues/170)
* [Syntax highlighting support](https://github.com/sebsauvage/Shaarli/pull/144)
* [Piwik tracking code integration](https://github.com/sebsauvage/Shaarli/issues/81)
* [Pingback support](https://github.com/sebsauvage/Shaarli/issues/75)