"I really worry about everything going to the cloud, I think it's going to be horrendous. With the cloud, you don't own anything. You already signed it away. I want to feel that I own things."
– Steve Wozniak, Apple Inc. Co-founder, 2012-07-04.
There is a natural synergy between FOSS and cloud computing, since FOSS solves the main concern about the cloud -- complete loss of control of software and data. Good open source cloud computing (OSCC) software is collected below. Please make sure any software you add has at least a basic development and user community.
Open source apps provided over the Internet.
 Document Management
- Alfresco - one of the first document management solutions.
- Nuxeo - scalable document management solution.
 Enterprise Resource Planning (ERP)
- OpenERP - widely used ERP solution.
- Opentaps - widely used ERP solution.
- CiviCRM - association and non-profit management.
- Collabtive - project management and collaboration.
- EGroupware - web-based groupware.
- OrangeHRM - Enterprise Resource Planning software.
- vTiger - customer relationship management.
Good data-center and cloud management open source.
 Data Centers
Buildings and infrastructure that serve large cloud solutions.
- Open Compute - an open source documentation project for scalable, efficient, and environmental data centers (started by FaceBook).
 Cloud Management
FOSS software to build and manage clouds.
- Deltacloud - an abstract cloud management layer.
- Juju - management of cloud services (from Canonical/Ubuntu).
- jclouds - abstracts multiple cloud API's with Java.
- Libcloud - a library that abstracts multiple cloud API's.
Good system level cloud open source.
 Distributed Computing
Distributed tools for very high load requirements, usually cloud scalability:
- Cassandra - scalable data replication and fault tolerance.
- Hadoop - processing of very large data sets across large numbers of computers.
- Mesos - application resource management across server clusters.
- Storm - distributed processing of very large data sets.
 Infrastructure as a Service
FOSS cloud virtual server management software.
- OpenStack - original FOSS cloud IaaS project.
 Operating Systems
Operating systems specifically configured for the cloud.
 Virtual Desktops
All software computer desktops over the Internet.
- FreeNX - the original NX compression software.
- neatx - Google NX compression.
- SPICE - Red Hat NX compression.
- x2go - x-windows compression.