Ganglia is a scalable distributed monitoring system for high-performance computing systems such as clusters and Grids. It is based on a hierarchical design targeted at federations of clusters. It leverages widely used technologies such as XML for data representation, XDR for compact, portable data transport, and RRDtool for data storage and visualization

collectd is a daemon which collects system performance statistics periodically and provides mechanisms to store the values in a variety of ways, for example in RRD files.

Cacti is a complete network graphing solution designed to harness the power of RRDTool's data storage and graphing functionality. Cacti provides a fast poller, advanced graph templating, multiple data acquisition methods, and user management features out of the box. All of this is wrapped in an intuitive, easy to use interface that makes sense for LAN-sized installations up to complex networks with hundreds of devices.

This is an entry point towards making Portuguese Government's data easily accessible for all.

The Visual Understanding Environment (VUE) is an Open Source project based at Tufts University. The VUE project is focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information.

Zebra is a high-performance, general-purpose structured text indexing and retrieval engine. It reads structured records in a variety of input formats (eg. email, XML, MARC) and allows access to them through exact boolean search expressions and relevance-ranked free-text queries.

The Echo Nest Remix API lets you manipulate music and video from the web. We've done the following: rearranged the syllables of a vocal line, walkenized and cowbellized hundreds of thousands of songs in a week, mixed up the hits of a drum beat and synced it to another loop, beat matched two songs, split apart DJ mixes by their individual tracks, made new kinds of music, synced a video to a song, transitioned between two covers of the same song, made a cat play piano. We're making this available as an open source SDK for Python that can currently be easily installed for Mac OS X and Linux. It accesses the Echo Nest Analyze API at http://developer.echonest.com seamlessly through a web services interface and parses the results. You'll need an Echo Nest API key to use this SDK.

Playdar is a music content resolver service - run it on every computer you use, and you'll be able to listen to all the songs you would otherwise be able to find manually by searching though all your computers, hard disks, online services, and friends' music collections.