Hi!
I've implemented in Wikibase, with the help of the Wikidata development team, a piece of code that allows to display an "Other project" sidebar managed by Wikidata as it have been done for interlanguage links [1]. This means that a link to Commons for example can automatically be added to a Wikipedia article's sidebar based on the data in Wikidata.
The goal is to replace the JavaScript based hacks used by a lot of wikis like nl.wikipedia that build such kind of sidebars from templates inserted in wiki text.
This new feature have been successfully deployed last Monday to French Wikisource. See, for example, this page [2] (the sidebar section is called "Autres projets" in French). I've also written a JavaScript hack that adds a link to Wikidata in this sidebar (it isn't supported yet by the extension) and that allows to override links using the old template in order to ensure a smooth migration.
If you want to see this feature installed in your wiki, please start a discussion on your local project chat and, when a consensus is reached, open a bug in bugzilla [3] (component: "Site requests") linking to the discussion and giving the ordered list of the sites to display (this can be one or several of "wikipedia", "commons", "wikiquote", "wikivoyage", "wikisource").
Feel free to ask if you have any questions.
Cheers,
Thomas (User:Tpt)