Facebook, Asana, Path and handful of other companies use Phabricator, primarily for code review: http://leanstack.io/phabricator. Also, Gitorious and Beanstalk are a couple of other options for code hosting (http://leanstack.io/code-collaboration-version-control).

The FreeBSD[1] project is using Phabricator currently[2], at least for the Ports tree code reviews, but it doesnt seem to be used as repository host (it sits on top of their SVN repo) but for the diff views, discussions, approval process and so on.

[1] https://www.FreeBSD.org/ [2] https://phabric.FreeBSD.org/

i've been using Phabricator as part of contributing to GHC this past month, and the tooling is REALLY nice (haven't used the repo bits, but i expect its pretty nice too)