During the course of the past few years the Hungarian Electronic Library became one of the most popular and most significant text-archives of the Hungarian webspace.

BackTrack is a Linux-based penetration testing arsenal that aids security professionals in the ability to perform assessments in a purely native environment dedicated to hacking.

Tungsten Replicator is a high performance, open source, data replication engine for MySQL. It offers a set of features that surpass any open source replicator available today: global transaction IDs to support failover, flexible transaction filtering, extensible transaction metadata, sharding, multiple replication services per process, high performance, and simple, well-documented operation.

C3 is a command line interface that may also be called within programs. The suite includes tools for cluster-wide command execution, file distribution and gathering, process termination, remote shutdown and restart, and system image updates.

ParaView is an open-source, multi-platform data analysis and visualization application. ParaView users can quickly build visualizations to analyze their data using qualitative and quantitative techniques.

The Transparent Inter Process Communication protocol allows applications in a clustered computer environment to communicate quickly and reliably with other applications, regardless of their location within the cluster.

Castle is a key-value store responsible for redundancy, caching, indexing and disk layout management. Acunu uses it to store all user data as well as statistics captured and displayed by the Control Center.
Castle is not cluster aware and thus it doesn’t participate in distributing data in a cluster. However, Castle interfaces are designed with distributed databases in mind, featuring timestamps and automated discarding of old, deleted data.

HTCondor is a specialized workload management system for compute-intensive jobs. Like other full-featured batch systems, HTCondor provides a job queueing mechanism, scheduling policy, priority scheme, resource monitoring, and resource management. Users submit their serial or parallel jobs to HTCondor, HTCondor places them into a queue, chooses when and where to run the jobs based upon a policy, carefully monitors their progress, and ultimately informs the user upon completion.

Softflowd is flow-based network traffic analyser capable of Cisco NetFlow data export. Softflowd semi-statefully tracks traffic flows recorded by listening on a network interface or by reading a packet capture file. These flows may be reported via NetFlow to a collecting host or summarised within softflowd itself.