EC2Dream Fogviz is a visual tool for building and managing cloud servers. It combines Fog, Ruby, and Chef into a tool that is particularly helpful when developing and testing Chef automation scripts. It currently supports Amazon AWS, Eucalyptus Cloud, and CloudStack including VPC, autoscaling, and the ability to list most entities., and Openstack clouds: Rackspace, HP Cloud, and CloudFoundry Open Platform.
BitNami Cloud Tools packages together Amazon Web Services tools with preconfigured Java and Ruby language runtimes to work out of the box. It is a self-contained, easy to use distribution with one goal in mind: to make it simple to get started using AWS services from the command line.
Apache Qpid is a messaging broker that implements the latest AMQP specification, providing transaction management, queuing, distribution, security, management, clustering, federation, heterogeneous multi-platform support, and much more. It is extremely fast and aims to be 100% AMQP Compliant.
OpenNebula is a toolkit to easily build any type of cloud: private, public, and hybrid. OpenNebula has been designed to be integrated with any networking and storage solution and so to fit into any existing data center. OpenNebula orchestrates storage, network, and virtualization technologies to enable the dynamic placement of multi-tier services (groups of interconnected virtual machines) on distributed infrastructures, combining both data center resources and remote cloud resources, according to allocation policies.
iExploder is like a fire hydrant full of bad HTML and CSS code to test the stability and security of Web browsers. It is available as a standalone Web server or CGI script. It continuously feeds browsers bad data in the hope that they will eventually crash. It is designed to run for hours, or even days until the browser crashes.
The Marionette Collective (mcollective) is a framework to build server orchestration or parallel job execution systems. It uses modern technologies and concepts that make it ideal for large and cloud-based infrastructures. It's specifically geared towards systems administration tasks, but can be seen as a generic framework too.