The ASF @ 15 - The Apache Software Foundation Celebrates 15 Years of Open Source Innovation and Community Leadership http://s.apache.org/wZr
... and cheered at ApacheCon Europe http://s.apache.org/1o4
The ASF is made up of more than 150 top level projects which cover a wide range of technologies. Chances are if you are looking for a rewarding experience in Open Source, you are going to find it here.
Apache Axiom is an XML object model supporting deferred parsing.
Apache Axiom is a StAX-based, XML Infoset compliant object model which supports on-demand building of the object tree. It supports a novel "pull-through" model which allows one to turn off the tree building and directly access the underlying pull event stream. It also has built in support for XML Optimized Packaging (XOP) and MTOM, the combination of which allows XML to carry binary data efficiently and in a transparent manner. The combination of these is an easy to use API with a very high performant architecture!
Apache Kafka is a distributed, fault tolerant, publish-subscribe messaging.
A single Kafka broker can handle hundreds of megabytes of reads and writes per second from thousands of clients. Kafka is designed to allow a single cluster to serve as the central data backbone for a large organization. It can be elastically and transparently expanded without downtime. Data streams are partitioned and spread over a cluster of machines to allow data streams larger than the capability of any single machine and to allow clusters of co-ordinated consumers. Kafka has a modern cluster-centric design that offers strong durability and fault-tolerance guarantees. Messages are persisted on disk and replicated within the cluster...
Forge software for hosting software projects
Apache Allura is an open source implementation of a software "forge", a web site that manages source code repositories, bug reports, discussions, wiki pages, blogs and more for any number of individual projects.