The Sonatype Nexus webpage says:
Sonatype Nexus sets the standard for repository management providing
development teams with the ability to proxy remote repositories and share
software artifacts. Download Nexus and gain control over open source
consumption and internal collaboration.
At work, we’re using Ant to manage our builds. We store artifacts from other teams in a common module. It would be nice to manage those external dependencies in a tool like Nexus.