Free and Open Source options
gitolite + cgit / trac
A fast, secure and stable solution based on Rails & Gitolite.
GitHub Enterprise includes the same great set of features as GitHub.com but packaged for running on your organization's local network. All repository data is stored on machines that you control, and access is integrated with your organization's authentication system (LDAP, CAS). Use GitHub Enterprise when you need complete control over repository and project information.
GitHub Enteprise is distributed in the industry standard Open Virtualization Format (OVF) only. Environments with official OVF support include VMware and VirtualBox.
Git Repository Management for Enterprise Teams. Behind the firewall Git management for your source. Create and manage repositories, set up fine-grained permissions, and collaborate on code – secure, fast and enterprise-grade.