Owncloud
From Jon's Wiki
Install:
git clone https://github.com/owncloud/core.git owncloud cd owncloud git submodule init # 3rdparty directory
There's a command-line tool for administering it:
sudo -u www-data php5 occ
Use this for upgrading point releases, adding/managing users, apps, etc. May need to disable non-core apps to do upgrades.